Implemented min_characters for free text answer
strip the answer when validating the min_characters
Implemented XBlocks validation on client side and submit button behavior based on it
Merge branch 'mcq-tip-popup' into answer-min-characters
minor fix for extra spaces
oups, indent-level-js was set to 2
Merge pull request #9 from aboudreault/answer-min-characters

Answer min characters