rename template tags to be more obvious
experiment with a collector process

The idea is to have a process similar to collecstatic, and
copy files in a temporary directory.

This avoid storage that use finders, streamline dev process with
production process, and make compilers easier to deal with.
update documentation
reintroduce python2.6 support
test against django 1.7c1
start documenting changes
style check
fix django 1.7 tests warning
test against Django 1.7
Document upgrade path.