CC-4961: Show linking

-initial schedule service experimentation
Added comments to Schedule Service
- Moved all form validation to it's own function in schedule service
- Moved show creation to it's own function in schedule service
Created show service
Created empty showInstance service.
Split populateShowUntil into 2 new functions: getPopulateDateUntil, and getShowDays
CC-4961: Show linking

Refactored some more show instance creation functions
CC-4961: Show linking

-initial schedule service experimentation
Added comments to Schedule Service
- Moved all form validation to it's own function in schedule service
- Moved show creation to it's own function in schedule service
Created show service
Created empty showInstance service.
Split populateShowUntil into 2 new functions: getPopulateDateUntil, and getShowDays
CC-4961: Show linking

Refactored some more show instance creation functions
Created function to create repeating show instances
Created function to create rebroadcast show instances
Merge branch 'cc-4961-show-linking' of dev.sourcefabric.org:airtime into cc-4961-show-linking

Conflicts:
	airtime_mvc/application/services/ScheduleService.php
	airtime_mvc/application/services/ShowInstanceService.php
	airtime_mvc/application/services/ShowService.php
Fixed rebroadcast date bug
Created function to set the next populate until date for repeating shows
Add comments
Refactored adding show forms to the view
Removed comment
Inital edit show reconfiguration changes