Split apart password and APOP auth, since some servers seem to do both,

Split apart password and APOP auth, since some servers seem to do both,

	* providers/pop3/camel-pop3-store.c: Split apart password and APOP
	auth, since some servers seem to do both, but don't really.
	(connect_to_server): Renamed from try_connect. Now actually does
	the connection up to the point of checking the greeting for APOP
	support.
	(query_auth_types): Return APOP, if appropriate. Call
	pop3_disconnect after connect_to_server since we don't really want
	to be connected.
	(pop3_connect): Use connect_to_server rather than duplicating
	code. Fix a one-byte buffer overrun in the APOP code.
	(pop3_disconnect): Make this able to clean up after a partial
	connect.