Remove the GUIDELINES file, which is replaced by section 4.3 of the
handbook a long time ago. Add a small README. It just refers refers people to section 4.2 and 4.3 of the handbook for now. It will be replaced with the all-dancing all-singing complete subdirectory-describin', tellin'-the-user-exactly- what-to-do version after 2.1 is out and I get some time!