* modest-tny-folder.[ch]:

	- add modest_tny_folder_is_local_folder, and
	- add modest_tny_folder_local_folder_type
* modest-local-folder-info.[ch]:
	- remove ModestLocalFolderType, use TnyFolderType instead
	- add some extra folder types
* modest-defs.h:
	- add display name for local folders (N_("Local Folders")
* modest-init.c:
	- adapt to these changes
* widgets/modest-folder-view.c:
	- display the display names for local folders

pmo-trunk-r735