convert None to bool before hashing, fixes #227
Improve depends= documentation.
Fix syntax error in test_filters.py.
Add global flag to Stylus installation note

Without the `-g` flag Stylus would be installed locally into `./node_modules`
include `manifest` setting in YAMLLoader

fixes #235
Add client-side Jade template filter.

Specifically, this filter compiles Jade templates into JavaScript
functions suitable for use in the browser.
Merge remote-tracking branch 'cederigo/master'
Merge branch 'master' into python3

Conflicts:
	tests/test_filters.py
Include six module with webassets.
Disable gzip filter on Python 3.

For now, anyway. I'm not sure if it's worth the effort to implement.
Remove overlooked print statements.
CoffeeScript filter output has changed.
Improve requirements file, fix version numbers.

Fix the version numbers of some external tools so that we will have
less trouble with ever changing filter output.
Sass filter: Remove deprecated include_dirs option.