keybinding support will be added later.
Add plugin functions for inserting text into the current document.
Add plugin support for disabling a menu item when no documents are
open.
Destroy plugin_fields->menu_item on unloading if set by a plugin.
Use G_MODULE_BIND_LOCAL for plugins to prevent symbol shadowing by
other modules, and to help detect unresolved symbols at loading time.


git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@1734 ea778897-0a13-0410-b9d1-a72fbfd435f5