r4345: Unify the representation of grouptype and samaccounttype to hex. Without any

kind of schema support we only have string comparisons (Hmm. Is this true?)
and must agree upon a common representation for integers. I suspect that we
might sooner or later need a search filter for "This bit in this integer
attrib is being set".

Volker
(This used to be commit 5f2d93b66bc89d499c91638f9b71394768d135af)