Fixing issue #23

Added initial impressum page.
Fixing issue #23

Changed impressum email address to info@gdg-dus.de
Changed organizer email
Merge remote-tracking branch 'origin/iss23' into gh-pages
Fixing issue #24

Added "this is a free event" information
Merge remote-tracking branch 'origin/iss24' into gh-pages
Revert "Revert "Fixing issue #24""

This reverts commit 2f71f6d262b6b7c8908aa52225431ef475973203.

Revert "Fixing issue #24"

This reverts commit
84eb9c778ff08a4eb723ad4868624f84ce3cb619.
Fixing issue #24

Again previously I started from wrong branch
Fixing issue #24

Enabled tickets.html block
Team page update
Added grandcentrix to partners
added gcx icon
Update _config.yml
removed CNAME
Revert "removed CNAME"

This reverts commit d85692033cc8a571b0abb78f5e047ef4f288439c.
Revert "Update _config.yml"

This reverts commit a3c6954f778be87181fc880551042e7fcb979d3a.
Merge pull request #25 from passsy/gh-pages

Added grandcentrix as sponsor
Add speakers and sessions

from
- Dittmar
- Frederik
- Pascal
- Wolfram
Remove timestamps from the unscheduled talks.
Add "GDG" ribbons to the speakers.