[FIX] Cache map of rooms per user

- Closes #1405
[FIX] Dummy conf for tests created in the past
[IMP] HTTP API - future events flag

- Tell whether there are future events or not
- Some PEP8
- Closes #1406
[IMP] Add modification date contrib to MARCXML

- Closes #1407
Merge branch 'v1.1'

Conflicts:
	indico/MaKaC/webinterface/rh/roomBooking.py
PEP8 fixes