better search for Objects in access rules

currently (5.0) the Objects have 2 forms
* the model name like "res.partner.title"
* the object name like "Partner"
search is only possible using the displayed name
searching in "Object" for res.partner should also return "Partner"
currently it is very cumbersome to add access rules

BTW - forbid duplicates of access rules
duplicates = having identical access rights

records should be sorted by object name or name