Added support for all natbib and BibLaTeX citation commands

[soraxas]

Modified the Regex for citation syntax, now it is able to capture all natbib commands and biblatex commands for citations.

natbib commands list
from https://gking.harvard.edu/files/natnotes2.pdf
biblatex commands list
from http://mirrors.ibiblio.org/CTAN/macros/latex/contrib/biblatex/doc/biblatex.pdf

Citations commands that wasn't capturing before includes:

%==========================================================%
%|                     Natbib Commands                    |%
%==========================================================%
\citenum{foo_bar}
\citetext{foo_bar}

%==========================================================%
%|                    BibLaTeX Commands                    |%
%==========================================================%
% Standard Commands
\Parencite{foo_bar}
\footcitetext{foo_bar}

% Style-specific Commands
\smartcite{foo_bar}
\Smartcite{foo_bar}
\supercite{foo_bar}

% Qualified Citation Lists

\Parencites{foo_bar}
\footcitetexts{foo_bar}
\smartcites{foo_bar}
\Smartcites{foo_bar}
\Textcite{aabide}
\supercites{aabide}

% Style-independent Commands
\Autocite{foo_bar}
\Autocite*{foo_bar}
\Autocites{foo_bar}
\citedate{foo_bar}
\citedate*{foo_bar}
\citeurl{foo_bar}
\parentext{foo_bar}
\brackettext{foo_bar}

% Special Commands
\volcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Volcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\volcites[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Volcites[hprenotei]{hvolumei}[hpagei]{foo_bar}
\pvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Pvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\pvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\Pvolcites[hprenotei]{hvolumei}
\fvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\ftvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\fvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\Fvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\svolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Svolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\svolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\Svolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\tvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Tvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\tvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\Tvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\avolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Avolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\avolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\Avolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}
          [hpagei]{foo_bar}
\notecite{foo_bar}
\Notecite{foo_bar}
\pnotecite{foo_bar}
\Pnotecite{foo_bar}
\fnotecite{foo_bar}

% Low-level Commands
\citename{foo_bar}[hformati]{hname listi}
\citelist{foo_bar}[hformati]{hliteral listi}
\citefield{foo_bar}[hformati]{hfieldi}

[soraxas]

The full list of citations commands used to validate the syntax highlighting:

%==========================================================%
%|                                                        |%
%|                     Natbib Commands                    |%
%|                                                        |%
%==========================================================%

\citet{foo_bar}
\citep{foo_bar}
\citealt{foo_bar}
\citealt*{foo_bar}
\citealp{foo_bar}
\citealp*{foo_bar}

\citenum{foo_bar}
\citetext{foo_bar}

\citeauthor{foo_bar}
\citeauthor*{foo_bar}
\citeyear{foo_bar}
\citeyearpar{foo_bar}

\Citet{foo_bar}
\Citep{foo_bar}
\Citealt{foo_bar}
\Citealp{foo_bar}
\Citeauthor{foo_bar}


%==========================================================%
%|                                                         |%
%|                    BibLaTeX Commands                    |%
%|                                                         |%
%==========================================================%

%----------------------------------------------------------%
%                    Standard Commands                     %
%----------------------------------------------------------%
\cite{foo_bar}
\Cite{foo_bar}

\parencite{foo_bar}
\Parencite{foo_bar}

\footcite{foo_bar}
\footcitetext{foo_bar}

%----------------------------------------------------------%
%                 Style-specific Commands                  %
%----------------------------------------------------------%
\smartcite{foo_bar}
\Smartcite{foo_bar}

\cite*{foo_bar}

\parencite*{foo_bar}

\supercite{foo_bar}

%----------------------------------------------------------%
%                 Qualified Citation Lists                 %
%----------------------------------------------------------%
\cites{foo_bar}
\Cites{foo_bar}

\parencites{foo_bar}
\Parencites{foo_bar}

\footcites{foo_bar}
\footcitetexts{foo_bar}

\smartcites{foo_bar}
\Smartcites{foo_bar}

\textcite{foo_bar}
\Textcite{aabide}

\supercites{aabide}

%----------------------------------------------------------%
%                Style-independent Commands                %
%----------------------------------------------------------%
\autocite{foo_bar}
\Autocite{foo_bar}

\autocite*{foo_bar}
\Autocite*{foo_bar}

\autocites{foo_bar}
\Autocites{foo_bar}

\citeauthor{foo_bar}
\citeauthor*{foo_bar}
\Citeauthor{foo_bar}
\Citeauthor*{foo_bar}

\citetitle{foo_bar}
\citetitle*{foo_bar}

\citeyear{foo_bar}
\citeyear*{foo_bar}

\citedate{foo_bar}
\citedate*{foo_bar}

\citeurl{foo_bar}

\parentext{foo_bar}

\brackettext{foo_bar}

%----------------------------------------------------------%
%                     Special Commands                     %
%----------------------------------------------------------%
\nocite{foo_bar}
\nocite{*}

\fullcite{foo_bar}

\footfullcite{foo_bar}

\volcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Volcite[hprenotei]{hvolumei}[hpagei]{foo_bar}

\volcites[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Volcites[hprenotei]{hvolumei}[hpagei]{foo_bar}

\pvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Pvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}

\pvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Pvolcites[hprenotei]{hvolumei}

\fvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\ftvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}

\fvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Fvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}

\svolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Svolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}

\svolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Svolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}

\tvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Tvolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}

\tvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Tvolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}

\avolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Avolcite[hprenotei]{hvolumei}[hpagei]{foo_bar}

\avolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}
\Avolcites[hprenotei]{hvolumei}[hpagei]{foo_bar}[hprenotei]{hvolumei}[hpagei]{foo_bar}

\notecite{foo_bar}
\Notecite{foo_bar}

\pnotecite{foo_bar}
\Pnotecite{foo_bar}

\fnotecite{foo_bar}

%----------------------------------------------------------%
%                    Low-level Commands                    %
%----------------------------------------------------------%
\citename{foo_bar}[hformati]{hname listi}

\citelist{foo_bar}[hformati]{hliteral listi}

\citefield{foo_bar}[hformati]{hfieldi}

[Aerijo]

Can't see anything wrong with it. The lenient [ANP]* at the end was there originally.