removed is_active from Host, Show and ProgramSlot.

program/admin.py

program/migrations/0009_host_remove_is_active.py

program/migrations/0010_show_remove_is_active.py

program/migrations/0011_programslot_remove_is_active.py

program/models.py

program/templates/host_detail.html

program/templates/show_detail.html

program/templates/show_list.html

program/views.py