Improved projector zoom and scroll behaviour.

Zoom and scroll the full content div (incl. title and sidebar).
Add zoom and scroll level in projector live view widget.
Fixed portable build error for pillow package. Updated create_portable.txt.
Add message if someone adds himself to the list of speakers. Fix #927.
Fixed #948: Use DIN A4 format and wlan ssid qrcode on access data PDF.
Merge pull request #952 from emanuelschuetze/zoom

Improved projector zoom and scroll behaviour.
Merge pull request #953 from emanuelschuetze/portable-fix

Fixed portable build error and updated create_portable.txt
Merge pull request #954 from emanuelschuetze/password-pdf

Use DIN A4 format and wlan ssid qrcode on access data PDF
Merge pull request #955 from normanjaeckel/Fix927

Add message if someone adds himself to the list of speakers. Fix #927.
Reenabeld the test for the QuestionView
Use sockjs instead of only websocket
Merge pull request #959 from ostcar/sockjs

Use sockjs instead of only websocket
Merge pull request #965 from ostcar/fixed_utils_view_test

Reenabeld the test for the QuestionView