set up basic guild and guilduser models and relationships
Set up basic controller, associations and routes for guilds
added some helper methods
Added Create, Edit, Update and Delete functions for Guild
Added functionality to edit Guilds for each user
Cleaned up code, added guild table, added admin rights.
Added Guilds as an additional sidebar option, included rake task, updated db:seed
To run rake db:add_guild_to_navbar_preference to add on this entry for existing courses
Cleaned up code and routes.
Minor fixes to code
fix sorting command
Removed unused methods
fix ability to allow guild to be viewed by students
Cosmetic changes: As a student to identify your own guild
Fix for guild leaderboard for empty guild
Removed redundant task
Removed redundant controller actions and mini code refactor
Used _form for the edit route
cleaned up naming conventions and fix routes
Merge pull request #296 from weiqingtoh/feature/course-groups

Implementation of Guilds in Coursemology
fixed mini spec naming issue