loadparm.c: Ensure printer services cannot be read only and don't use share mode...

loadparm.c:	Ensure printer services cannot be read only and don't use share mode locking.
locking.c:	Changed aborts to returns so not so drastic on PANIC errors.
proto.h:	Removed definition of open_file as this is now never externally called.
reply.c:	Changed reply_mknew, reply_ctemp, reply_printopen to go through open_file_shared.
server.c:	Modified open_file_shared to be more robust and be useful for printer & temp files.
		Removed truncate option from open_file (now all truncates are done in open_file_shared).
util.c:		Added EAGAIN to errors checked in open_socket_out().
version.h:	Updated to 1.9.17alpha2.
jallison@whistle.com