Review 52a38d55097bf0532b0eaa97552e001203808e88

Review 52a38d55097bf0532b0eaa97552e001203808e88

	* Changelog: Update documentation of 2013-07-28  mancha entry.
	* lib/prototypes.h, lib/encrypt.c: Update splint marker,
	pw_encrypt can return NULL.
	* lib/encrypt.c: Fix outdated statement on GNU crypt.
	* src/chgpasswd.c: Improve diagnostic to user when pw_encrypt
	fails and use fail_exit() instead of exit().
	* src/chpasswd.c: Likewise.
	* src/newusers.c: Likewise.
	* src/passwd.c: Likewise when new password is encrypted.
	* src/newgrp.c: Improve diagnostic to user and syslog when
	pw_encrypt fails.  Do not apply 1s penalty as this is not an
	invalid password issue.
	* src/passwd.c: Likewise when password is checked.