Localize and rename ACL configuration.

This is more-or-less a reversion of previous ACL behavior so that
it is more self-contained. ACL sections are now only parsed if res_pjsip_acl.so
is loaded. Moreover, the configuration section is now "type=acl" instead of
"type=security".

The original reason for having ACLs configured in a "type=security" section
was to lump ACLs and other security-related items into the same section. The
problem is that ACLs really should be in their own sections and there are
no other security-related options implemented anyways.



git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@397193 f38db490-d61c-443f-a65b-d21fe96a405b