#255: Added a dark-background highlight.  It isn't perfect, but it is better
Merge branch 'dark-theme-highlight' of github.com:hughfdjackson/idris-mode into hughfdjackson-dark-theme-highlight
Add more settings for idris loaded region face

Now it should be a bit more sensitive to different kinds of
terminal. Tested in a few themes locally.
Merge pull request #266 from david-christiansen/hughfdjackson-dark-theme-highlight

Dark theme highlight for more terminals