Move SQLite and SFTPPlusWebAdmin handlers into server

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Move SQLite and SFTPPlusWebAdmin handlers into server.

Problem description
===================

We want to move SQLite and SFTPPlusWebAdmin log handlers out of the commons repo into the server repo. Only the server needs to use the specialized handlers.

Changes description
===================

Removed all code pertaining to SQLite and SFTPlusWebAdmin handlers.

How to try and test the changes
===============================

Check that all tests pass.
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