r7626: a new ldap client library. Main features are:

r7626: a new ldap client library. Main features are:

 - hooked into events system, so requests can be truly async and won't
   interfere with other processing happening at the same time

 - uses NTSTATUS codes for errors (previously errors were mostly
   ignored). In a similar fashion to the DOS error handling, I have
   reserved a range of the NTSTATUS code 32 bit space for LDAP error
   codes, so a function can return a LDAP error code in a NTSTATUS

 - much cleaner packet handling
(This used to be commit 2e3c660b2fc20e046d82bf1cc296422b6e7dfad0)