* add a checkbutton to use the entered nickname by default without asking anymore. Fixes #5141

don't remove occupant from room roster when we try to change our nick to the occupant's nick. Fixes #5120

* 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