WIP: v1.1.0

Luuk Scholten
2016-12-14T21:13:53+01:00

## Errors resolved
- [x] Fix sitemap and 'preview on page' of partners by fix resolving absolute url for partners (!243)
- [x] Add missing fancybox images (!244)
- [x] Fix permissions for sending newsletters ,no longer superuser required (!250)
- [x] Fix problem with user mailaddress when sending a newsletters (!252)
- [x] Only show active committees that the user is a member of in events admin, when selecting organisor (!245)
- [x] Fix check for overlapping memberships and chairs to work correctly (!246)

## New functionality
- [x] Events: add notition that registration is required if you fill in a registration period, otherwise not (!238)
- [x] Enable fancier permission selection field (!251)
- [x] Sort committee memberships by starting date on profile page (!255)
- [x] Add checkbox for the costs warning to newsletter events (!254)

## Technical changes
- [x] Log errors to Slack instead of email (!242)
- [x] Fix broken migrations for committee chairs (!247)
- [x] Add management script to clean emails (!253)