Bug 686606 - Add a few translator comments
Bug 699338 - Only show plugin tooltip for errors
Remove extra semicolon in G_DEFINE_*
Use AM_CPPFLAGS instead of INCLUDED

INCLUDES is deprecated and AM_CPPFLAGS should be used instead.
Small function pointer cleanup
Fix i18n support by adding back ENABLE_NLS.

https://bugzilla.gnome.org/show_bug.cgi?id=727501