* Add GEANY_ prefix to enumerators.
* Use a discrete set of enumerators so the proxy doesn't have to
worry about flag bitmasks, which isn't required.
* Update documentation.
* Use the new enumerators in Geany.
* Improve debug output for bogus values a bit.
This demo proxy does not actually do anything useful. It simply loads
pseudo-plugins from an ini-style file. The point is that there will be a plugin
in the PM dialog for each ini. Each ini-plugin also causes a menu item to be
generated.