Terms of service

NOTE:
ToS appear to only work in Firestorm or derivatives.
Singularity and derivatives appear to have the second life ToS
hardcoded.
- Additional processing for supplied ToS configuration
- Enable use of html format ToS
- Sample text and html ToS files
- Correct inclusion in the WebUI registration page
Web welcome message setting

- remove setting of the Chat message as this needs to be treated
differently than the initial greeting message
Region profile picture

- Check for an enabled worldview module before inclusion