[MonoDevelop] text editor changes

[John Luke]

Hey all,
I just committed into svn support for Edit Actions to control the
key press handling in the text editor.  If you notice anything is
broken (that wasn't already prior to svn r51875) please let me know
or file a bug in bugzilla.

AddIn authors should now be able to customize the text editor by
either implementing IEditAction or inheriting from AbstractEditAction
and override the Execute method.  The key an action occurs on is defined
in the addin file like so:
<EditAction id = "DeleteLine" class =
"MonoDevelop.SourceEditor.Actions.DeleteLine" keys = "Control|k" />