Added getFavorites method to QuestionServiceInterface. Added equals and hashcode functions to Question and Solution classes.
Merge pull request #27 from dcs24/master

equals, hashCode, and getFavorites
Refactored enum and interface names
Added skeleton code for QuestionService.java
switched to Jackson 1.9
Merge pull request #34 from kevinloh/master

Finish implementation for Question and Solution. Refactored enums and interface for better style.
switched to use java.util.Date
WIP: fleshing out QuestionService