Reduce the number of requests to SisA when creating the calendar.
Reduce the number of requests to SisA when creating the calendar.

This closes #9

Their used to be 3 requests each time:
 1. Get request to the calendar, to initialize things
 2. A post to switch to the list view
 3. A get to request the list view

The first two steps are now when logging in, so they are done only once.

nathansamson/sisacal