[TASK][DOC] Basic glossary of LDAP terms

Resolves: #60206
Change-Id: I4a4a80390511d6c042281f18fab39b906eb93c0d
Reviewed-on: https://review.typo3.org/31629
Reviewed-by: Thierry Brodard <thierry.brodard@techniconcept.ch>
Tested-by: Thierry Brodard <thierry.brodard@techniconcept.ch>
Reviewed-by: Xavier Perseguers <xavier@typo3.org>
Tested-by: Xavier Perseguers <xavier@typo3.org>