Set a baseUrl for the current installation.

Removed unused properties. We need only logic to get the data here.
Make the Twypo Instance available as TWYPO for any plugin.

We can later use this as a basic API interface.
Use the new API interface to pass data to Twypo.
Get the current page Url via TypoScript.
Fix the current page Url.
We don't need this data anymore.