Add better grammar definition
Changed interface
.txt extension ignored by git

The .txt extension is reserved for program input files (i.e. prosamm
reading material, Wikipedia articles, etc.). These should not be
committed.
Remove test files from main project
Stop execution if questions could not be parsed
Removed terminal output
Initial new generator infrastructure
Changed back interface
Merge branch 'master' of github.com:ai14/prosammgen into new-generators
Use new grammar in rest of app
Merge pull request #15 from ai14/new-grammar

Add better grammar definition
Merge branch 'master' of github.com:ai14/prosammgen into new-generators