[source] small refactoring to avoid being doomed by a wrong assertion message on buggy storage raising attribute error

[twisted] fix LongTimeExpiringFile and getChild implementation

merge

fix cwctl db-init -d on SQL Server

[repository] fix edited_attributes management in multiple SET queries entity.edited_attributes was messed up with previous edited entities. The UpdateStep now gives a new fresh edited_attributes set to repository.glob_update_entity() so that each entity can modify it during its "transaction".

[testlib] fix dummy bug in reset_test_database(): s/if/elif

merge