Add API & admin support for holiday schedules.

API support is only read for now.
Merge pull request #263 from codeforamerica/holiday-schedules-admin

Add API & admin support for holiday schedules.
Add holiday schedules to example location.
merges holiday schedules commits
Simplifies location form
assocaite schedules with availabilities
add localalisation for contact
half way to availability fe
allow editing of admin emails in organization
nullify blank admin_emails for organization
allows selection of available locations from service form