ADDED user and skill id validations to proficiency_spec
Added user can only have a given skill once sudo code
commented out given skill sudo code before pull request
UPDATED proficiency and test cases
ADDED api url for users
MOVED rabl_init to initializers folder; UPDATED user api
ADDED validation to role in users api
UPDATED api root route
UPDATED seeds.rb
ADDED username field to AddFieldsToUsers db
ADDED create_username funtion to user.rb and ADDED working test to user_spec
ADDED username becomes all lowercase
UPDATED conversation and message model
ADDED conversation, skill, proficiency, message routes to api
ADDED involve_user method in conversation
UPDATED seeds.rb
Merge pull request #23 from Simon245/username

Username
Merge remote-tracking branch 'origin' into API
ADDED delete current user, ADDED destroy fuction to user controller and tests
ADDED involve_user filter method to apprenticeship