Enable OPIE by default, using the no_fake_prompts option to hide it from

Enable OPIE by default, using the no_fake_prompts option to hide it from
users who don't wish to use it.  If the admin is worried about leaking
information about which users exist and which have OPIE enabled, the
no_fake_prompts option can simply be removed.

Also insert the appropriate pam_opieaccess lines after pam_opie to break
the chain in case the user is logging in from an untrusted host, or has a
.opiealways file.  The entire opieaccess / opiealways concept is slightly
unpammish, but admins familiar with OPIE will expect it to work.

Reviewed by:	ache, markm
Sponsored by:	DARPA, NAI Labs