begin preparing instructor constraint screen
add before after check
add time/day, time, and day dropdowns to GUI
add GUI skeleton for instructor constraints
add day_code checkbox functionality
separate priority check into helper function
add before/after timeslot adjustment in instructor time constraint
prepare add constraint button code to link to constraints
adds section logic and batch processing
Merge branch 'constraints' of https://github.com/donnell74/CSC-450-Scheduler into constraints
make day_code lowercase, rename course time constraint function
prepare a frame for viewing added constraints
Pass list of constraint objects to ConstraintPage.
Add view constraints button for the Constraint Page.
Make Constraint page scrollbox update when user clicks Add Constraint.
Adding the instructor preference before/after
Merge branch 'constraints' of https://www.github.com/donnell74/CSC-450-Scheduler into constraints
add instructor preference day constraint
Merge branch 'constraints' of https://github.com/donnell74/CSC-450-Scheduler into constraints
add Renato's constraints, fix priority bug