Provide simple library reference info directly within the IDE

[lmihalkovic]

Builtin libraries have nice, simple reference pages on the arduino.cc web site. It might be nice to present this information directly in the IDE (I tested with the current Wire library, however the page contains dynamic behavior that does not render gracefully as it is).

This could be done in several ways

• at the minimum, have a link in the library.properties file that the IDE can use to open externally, in the default platform browser, when the user right-clicks on the library's name in the outline view.
• a more elaborate support could be to include a single page doc.rtf per library, which the UI can display in a popup, with the same or similar triggering. Alternatively the file could be a simple .html file.
• at the cost of more implementation work, each library could have a doc folder containing a series of html files, with no external links. The IDE could have a template CSS file used for all help files.

Outline view:

[lmihalkovic]

Right click on a library reference node give the following popup menu (don't mind the first 2 entries, it is to test external menu contributions inside the outline view)

Clicking "library reference" opens the manual for that library

TODO:

• would be nice if a "reference" field was added to library.properties
• would be nice to support doxygen for contributed libs
• would be nice if the reference url for platform libs could target a subset of the complete page that does not include the arduino web site header
• store the last know placement of the help browser for each editor separately?
• provide coloring based on the current editor selection (?? dunno if worth it)

Currently the browser is using this hardcoded base for accessing the reference info for all the platform libraries... :-(

  static String BASE = "http://www.arduino.cc/en/Reference/";

[lmihalkovic]

Done