GitLab

- Rename Logger to MessageArchiveStorage
- Move into storage module
- Inherit from SqliteStorage

- Add Storage base class
- Move Cache code into own module
- Simplify roster cache

Fixes #10146

We have a setting in the Accounts Window now

Previously only application default values were possible

This helps the Window Manager decide how to display the window

This is a more flexible approach

default_text is returned if the value of the setting is an empty string