Receiving texts now only uses arvin's module.

- Modified Arvin's module to also give time of the message
- Put all of David's old function for receiving texts into a hook
  to Arvin's module.
- Cleaned up some unnecessary code, integrated conditions on alarm
  into the database query.
- Moved the answer checking functionality into its own function; we
  may want to make it more robust/sophisticated later.
- Added ability to check all alternative answers (NOT TESTED)
- Removed the vast majority of debug messages; they are not useful
  in this situation since it is no longer a function run on a page.
- removed most ui hooks to functions in receive_texts; they are no
  longer applicable.
- Other minor changes to code style and structure.