add controversy sorting to proposals
correct indentation and fix calculation
add an explanation to the contoversy algorithm
Fix calculation
better doc
correkt spelling
clear Superfluous spaces
Revert "Move FriendlyFormPlugin into adhocracy code (Preparation for #352 and general improvement of the login form)"

This reverts commit 45038d7a6afd6decf4781035e19d3aa9f2b700f8.
It turns out that we don't need to change the FriendlyFormPlugin to get proper came_from semantics, at least not immediately.
Do not use bytestrings in tests

This is an ongoing effort to squelch the "Unicode type received non-unicode bind param value" warning.
Add controversy sort

See hhucn/adhocracy.hhu_theme#129 . This commit contains work of Tobias Escher and @wawe.
Closes #258