As proposed in #113, this PR implements changes in the delegation handling logic in computer.py and memberships.py. The changes implemented are as follows:

• If the object is referenced by SID (check logic unchanged), the object is resolved via existing method resolve_sid().
• If the object is referenced by another name, it is split and resolved by its samAccountName via resolve_samname().
  • Since we aren't sure of the exact samAccountName (could be USERNAME or COMPUTERNAME$ for example), the allow_filter flag was introduced to allow the use of LDAP wildcards in the resolve_samname() function.
  • The check for a period (".") in the name has been removed, since this could cause issues in cases where a user (not a FQDN) is allowed to delegate. To avoid duplicates (e.g. "HOST" and "HOST.fqdn" both appearing), a variable called delegatehosts_cache is introduced to keep track of hosts that have already been processed.
• After resolving the object, the resolve_ad_entry() function is used to get the object's properties. If a samAccountName was used before, the resolved object properties are used to translate that back to its objectID.

Tested to work in my environment. Also tested with the latest version of bloodhound_import (fox-it/bloodhound-import@d52c24f), closing referencing PR fox-it/bloodhound-import#37.