update Challenge model and model tests to not require test_code value
alternative layout for landing page
styling checkin
change error reporting for multiple errors
styling: landing page update and employee show
styling: employee show, new, edit
styling: interview show
styling: refine interview show, feedback
styling: challenge new, company show, employee new
styling: company show and adding items to the company
styling: landing page
Fix error messages
Todo comments in ApplicationController
Todo comment in Checkins controller
Reordering + bug comment
Refactor + todo comments on InterviewsController
Add pending tests to write
Add basic tests for ApiController
Write tests for CandidatesController + refactor to make them pass
Fix :test_code bug