Fixed heroku error on using  unknown reward
Request validation implemented
Added response to validation
Users list allowed only for admin
Code reformatted
Added validation to checkins controller
Added @usernot null check in request validation method
Fixed validation, renamed passed user id parameter to uid
Typo fix
single uset GET:Added if uid & id match
Added error messages and codes on weird behavior
Refctored error messages
No idea what im commiting