Improve LDAP connection configuration in ldap.connect()
Improve LDAP connection configuration in ldap.connect()

Group the different options together. This will make adding new options
easier.

In addition, the `auto_bind` and `lazy` options are no longer hard
coded.

wylee/django-arcutils,PSU-OIT-ARC/django-arcutils,wylee/django-arcutils,PSU-OIT-ARC/django-arcutils