WebDeposit: file renaming and cleaning

* Fixes broken plugins logging.

* Removes unecessary error logging when trying to load
  plugins from `__init__`

Co-authored-by: Konstantinos Ntemagkos <konstantinos.ntemagkos@cern.ch>
Co-authored-by: Tibor Simko <tibor.simko@cern.ch>
WebDeposit: `db.func.max` call fix

Reviewed-by: Jiri Kuncar <jiri.kuncar@cern.ch>
WebMessage: blueprint name renaming
WebAccount: blueprint name renaming
WebGroup: blueprint name renaming
WebSearch: fix encoding and caching

Reported-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
WebStyle: fix POST request for mp_legacy_publisher