2007-01-16 [colin] 2.7.1cvs8

	* src/filtering.c
		Bigger buffer for errors
	* src/imap.c
	* src/imap.h
	* src/imap_gtk.c
	* src/prefs_account.c
	* src/prefs_account.h
	* src/wizard.c
	* src/etpan/imap-thread.c
	* src/etpan/imap-thread.h
	* manual/handling.xml
		Add subscriptions management. What it changes:
		Creating a folder subscribes to it
		Deleting a folder unsubscribes it
		New contextual menu item allowing to switch between
		All folders and Subscribed folders, subscribe, and
		unsubscribe. "Creating" an existing but unsubscribed
		folder will subscribe it.
		By default for new accounts, only subscribed folders
		are shown.