[BUGFIX] mssql: Proper types inserting / updating rows

MS SQL server is more picky about types than postgres and
mysql. This is especially true for LOB columns - even empty
strings need a proper cast and specific handling.

Various parts of the core deal with arbitrary tables and
don't know if a column is int, text or lob, or whatever.
Those are blindly updated / inserted, resulting in mssql
saying "no".

Solution is to fetch column schema and to set proper types
based on that schema. This is expensive. We will have to
refactor that again, and we will probably end up with a
(cache?) entry that knows the entire table schema of an
instance.

Solving that in a good way would also fix various mysql strict
issues we still have in the core. However, this needs more work.

Goal of the current patch is to bring mssql to a working state.
The solution must be seen as hacky, but is restricted to that
platform only and can be relaxed and improved as soon as we
take the next steps with schema handling in the TYPO3 cor...