Add support for LDAP options and TLS connection.

Two extra keys should be specified in DATABASES['ldap']:
'TLS': True/False
'CONNECTION_OPTIONS': dictionary (like AUTH_LDAP_CONNECTION_OPTIONS in django-auth-ldap)
Add more values in settings
use a dedicated logger for ldapdb logging
Merge pull request #7 from tampakrap/ldap_connection

Add support for LDAP options and TLS connection.
update copyright notice
update copyright notice
cleanup urls
fix pep8 errors
force line breaks in README.md
support django 1.5, don't support 1.2
CONNECTION_OPTIONS is a dict, not a list
Add FloatField, similar to IntegerField
Add test for FloatField
FloatField should inherit django's FloatField, not IntegerField
Implement DateField to access arbitrary dates
Add test for DateField
Close LDAP connections properly.

Implement the close() method in DatabaseWrapper so that the connection
to LDAP is actually unbound and closed properly as necessary.
fix django 1.2 and 1.3 compatibility
Merge pull request #12 from mgorny/close-connections-properly

Close LDAP connections properly.
fix django 1.2 and 1.3 compatibility