renamed README to README.rst

--HG--
rename : README => README.rst
moved subprocess import in yuicompressor to get_output, so pure App Engine users (without Django-nonrel) won't run into problems
updated to new pyjamas repo version
updated to improved pyjs native_js_func API (more future-proof)
added "ico" file type to CopyFiles generator
added support for HTML5 offline manifest generation
added swf to CopyFiles
fixed Sass support on Linux
fixed platform detection. the platform module always returns "Linux" with the GAE SDK
raise Http404 on unknown file (otherwise you won't get rid of the manifest...)
added media_url() JS function and filter
fixed order of root filters. yuicompressor should come after concat
added filter for Closure compiler
updated pyjs filter to latest repo version
bumped version
added changelog to readme
fixed media_url JS filter
CopyFiles generator can now ignore files matching a certain pattern
updated changelog
added Template filter (runs through Django template), contributed by Matt Bierner