Merge pull request #63 from guywyers/master

Support for OpenVPN Challenge/Response protocol

Tag auth-ldap-2.0.3

Tag 2.0.2, now with referral following disable support

Tag 2.0.1, again

Tag 2.0 Release.

Tag RC3

Tag 2.0-rc2. Only change is bindDN support

Tag the first 2.0 release candidate from branches/auth-ldap-2.0

Tag 2.0 beta3

Tag beta2