Update auth.inc.php

Optional ldap auth protocol version
(fix ldap_bind(): Unable to bind to server: Protocol error if used >2 protocol version)
Update config-me.inc.php

added $ldap_proto parameter
Declare missing syslog variables

Currently only used to log successful authentication in this function.
I'll add logging for failed attempts in later commits.
If syslog enabled, log all types of LDAP authentication failures.
Refactor syslog logging into new function
Merge pull request #154 from alexjfisher/ldap_syslog

Ldap syslog
Fixes #89 - Introduced natural sort order for zone listing.
Merge branch 'master' of https://github.com/poweradmin/poweradmin
Merge remote-tracking branch 'karamelichkin/patch-1'
Merge remote-tracking branch 'karamelichkin/master'

Conflicts:
	inc/config-me.inc.php