Debug messages only
model: Provide a method to get words matching a regular expression
WPSView: Refresh list of words once a word is deleted.
model: restart letter index if current word is being deleted
Merge pull request #28 from CS673/vivek-model-fixes-2

Vivek model fixes 2
Remove unused imports.
Hook up letter choice pulldown menu.
Merge branch 'word-search' of https://github.com/CS673/Awesome-Alphabet into word-search