Finished implementation/tests of proper error messages for unmatched
routes
Better formatting for error messages
Changed error context to use the new MatchError struct. Updated the
tests to reflect this. Removed old context key values and added a new
single one that contains the error struct.
Removed body messages from default errors
Implemented Kamil's suggestions.  Also removed another method that is
now no longer being used (mapListToString)
merge for test