Feature changes --
	- When program is being announced, allow the user to specify locality, as well as timings for the program
	- Allowing user to specify custom payment amount for venue
	- Teacher will now specify availability slot independent of the program type
	- The timing slots have been modified (seed data change)
	- if a part-time teacher has to be enabled as co-teacher
		-- the part_time_co_teacher flag should be set <-- one time, training dept
		-- now the center scheduler can add the person as co-teacher for classes happening in the center, for program where co-teacher is allowed
	- if a part-time teacher has to be scheduled for ashram program
		-- the part_time_co_teacher flag should be set <-- one time, training dept
		-- ashram has to be added as a center to the teacher centers <-- one time, super-admin
		-- ashram scheduler should be enabled as full_time_teacher_scheduler for the zone - with which teacher is associated <-- one time, super-admin
		-- teacher has pubish schedule (available for all slots in a day) for ashram center (same as how he does for other centers).
	- Once program ready for announcement, you cannot add more venue to the program.
	- Cleaning up the "IS NULL" logic

Schema changes --
    add_column :program_types, :session_duration, :integer
    add_column :venue_schedules, :payment, :integer
    remove_column :teacher_schedules, :program_type_id
	add_column :teachers, part_time_co_teacher, :boolean, :default => false
    add_column :programs, :announced_locality, :string
    add_column :programs, :announced_timing, :string

Seed data changes --
. Timing slots have been modified to cover almost the whole day from 6 am to 10 pm
Merge remote-tracking branch 'origin/amit' into amit

Conflicts:
	app/models/program_teacher_schedule.rb
	app/models/teacher.rb
	app/models/teacher_schedule.rb