- Move common fields from Contact & Sales_rep to  class Person.
- Modify Contact spec according to that ^^^ .
- Add Sales_rep Model & Spec.
ostly view changes.
Assing sales_reps to Client meetings is on progress
Final commit, will change app architecture.
- Add 'simple_form' gem.
- Add MeetingsController.
- Add MeetingController#index, and view.
- Edit meeting, New meeting with assigned sales_reps works!
- list Sales_reps in the meeting _form as checkboxes so the user can assgine Sales_reps .
- Modify MeetingsController#new, #create according to that ^^.
- Add better error gem.
- Mostley view changes (Meeting, SalesReps).