Add ber_get_enum() for symmetry

Need to add lber-types(3) to document BER types, allocation, and deallocation.
May need to add additional pages to document other new features.

Submitted by Gabor Gombas <gombasg@inf.elte.hu>

must be specified for each database.

code has been committed.
Add item to implement SASL/TLS to clients.
(This is not to imply that the code is complete)

Used only for simple bind when dn == NULL and password != NULL.

Modify tests to use -h "ldap://localhost:port/" instead of -p port.

user password.  Likely to be modified to use bind control
instead.  Use of modify deprecated in favor mechanisms that
support passwords stored externally to the directory (such
as in a SASL service).
Modified slapd extended operation infrastructure to support
backend provided extended operations.