Add Arduino support

[liamhays]

Hello! Awesome project, very fast, much colorful. Can you add support for .ino (Arduino) files? All the program needs to do is identify them and use standard C coloring (or C++, but see doesn't seem to have syntax highlighting for .cpp or .cxx).

[guilhermeprokisch]

@liamhays sorry for the late reply. I will check this when I got some time.