Added active_model_serializer gem
Added group, employee, and request serializers
Rescue from ParametersMissing
Rescue from AccessDenied
Rescue from RecordInvalid
Added Groups controller
Added Employees controller
Added Requests controller
Added Request toggle
Added Requests create_many
Set REST routes explicitly with `only` instead of `except`
Re-organized api controller tests
Merge branch 'api'