bump kaminari

(cherry picked from commit b5e6c2a149d0e7f84193ac08cd7b9d10af5662de)
embedding youtube videos over https

(cherry picked from commit 1563d088bc8ff4aa7b44fe9c1d3bdf4f0e83f0be)
fix regression caused by updating backbone.js without updating changed parameters

(cherry picked from commit 09a840ea418b0a3e567a495da79abdf3f87f748c)
fix hovercards

(cherry picked from commit a51c4f0ddccea1a8010d058b8de3281f73442ac4)

Conflicts:
	Changelog.md
Changelogs for 0.3.0.2, changelog for #4714
Bump version to 0.3.0.2
Merge branch 'hotfix/0.3.0.2'
update rails to 3.2.17
Merge branch 'hotfix/0.3.0.3'
Merge remote-tracking branch 'upstream/master'
imprintlink
Merge branch 'master' into ruhrspora