Added method LDAPObject.supported_ldap_version()

[Michael Ströder]

HI!

I've committed a method LDAPObject.supported_ldap_version() to
Lib/ldap/ldapobject.py in CVS.

See the code snippet below. Please comment whether you find it
useful or annoying. Personally I'm using this code in web2ldap for
quite some while now and it seems to work with LDAP servers from
several vendors.

Hmm, I also thought about placing something like this in
LDAPObject.bind() to avoid an extra BindRequest. But this might be
too much hidden magic.

Ciao, Michael.