Prepared diff view for multiple view modes

Converted commits.js to coffeescript
image info in separate coffeescript file

Added swipe view mode

Added onion skin viewMode

switch to use link_to_member to prevent 500 if user is a project owner but does not have membership and leave comment

Allows previews and uploads in all forms.
Also fixes #1730

-`remove comment` button will not make the text jump anymore.

Merge branch 'master' into non-interactive-aws-install

Conflicts:
	doc/installation.md

Fix merge mess in installation.md