Added tests for authentication_engine. IN-6
Added attr_accessor for authentication engines. Authenticate method will set this if a user is found. IN-6
Extracted code for retrieving authorization from HTTP Header to lib file. IN-6
Including HttpHeader module. IN-6
Extracted random password creation to model file. IN-6
Cherry pick commit and fixed conflict
Initial work moving authentication pieces for LDAP into LdapEngine. IN-6
Using the auth_engine's user login instead of proxy user. IN-6
Cleaned up code for HTTP Basic engine. IN-6