Do not enable adopt polls by default in new instances
Do not enable norms by default in new instances
Allow to hide norms navigation item

Conflicts:
	src/adhocracy/controllers/instance.py
	src/adhocracy/model/instance.py
Update knockoutjs (2.1.0 -> 2.2.1) and knockout.mapping (2.2.3 -> 2.4.1)
Request adhocracy_ko resource outside of tile (fixes #427)

Tile caching can leed to fanstatic resources not being requested if a
template isn't rendered but taken from the cache.

This happens in the show proposal page, which includes selection tiles,
which need adhocracy_ko, which is missing if the tiles are taken from
the cache.

This commit therefore makes sure the fanstatic resource isn't requested
from within the tile.
Fix changing norms from within proposals (fixes #406)

The behavior of PickleType has been changed in SQLAlchemy 0.7 such that
changes of such attributes aren't detected automatically anymore. This
commit restores the previous behavior.

This needs to be touched again when moving to SQLAlchemy 0.8, as the
mutable flag will then be removed and we have to create a custom data
type for the variants list, which inherits from the `Mutable` mixin.