Update README: add bash example for setting dir
make geometry switch override the config file

Closes #69
add license header to termite.cc

Addresses issue #68
Smarten and add color to possible hint matches

Changed URL hinting to be a lot smarter and to color hints when
possible matches are found.

- Add active_foreground and active_background config options

- Add a new char* to hold entry text for checking against when redrawing

- Add GTK_KEY_BACKSPACE to catch deletions