* fixed some problems with SQL escapement for roster versioning. For example when we have double quote or another character like this. Fixes #5159
* some code refactoring for roster versioning in common/logger.py
* added a docstring and some comments in common/logger.py

restore metacontct correctly when we connect to server and we already have contacts in roster (stored locally). Fixes #5156

handle correctly when MUC server force us to change our nickname by sending a 303 error presence. Fixes #5055

* fixed a bug when we remove a contact from our contact list (before we did not remove contact from roster_group table)

* now there is no more sparkling when we update the RosterWindow with the roster received from the server (when server does not handle roster versioning or when it resends the whole roster)

* In order to allow the viewing of the roster when we are offline (and some other cool stuffs), with and without roster versioning, now we load roster when RosterWindow is created (at gajim startup). Fixes #3190