Merge branch 'release/0.8' into stable
Merge branch 'release/0.9' into stable
Cleancss as an input filter to fix import inlining

cleancss is the only webassets filter(AFAIK) that supports CSS import inlining. But to do that it needs to know the directory path of the CSS file it's working on, which is only accessible to input filters.

We provide an input function that passes the --root argument to cleancss to fix this issue.

We keep the output filter as an added bonus to remove new lines between files processed this way.
Support files lists or tuples in Jinja2 assets block.

E.g.: `{% assets 'f1', ('f2', 'f3'), ['f4'] %}`
renders like `{% assets 'f1', 'f2', 'f3', 'f4' %}`.

It helps assets composition, enabling something like *varargs
(not supported by Jinja2).
escape JS string literals correctly in JST filter
Add autoprefixer support.
Fix options dict.
Merge branch 'add-autoprefixer' of https://github.com/YesGraph/webassets
fixed webassets issue #286 (and switch I/O to binary-mode)
added unit test for fix to issue #286
changed python loader to allow custom environment name
removed lines from test file
cleaned up the code and removed a print statement
forgot a second print statement
Merge branch 'prefixed-python-loader' of https://github.com/ahlen/webassets
Merge pull request #287 from metagriffin/feature/issue-286

fix for issue #286 (ExternalTool not re-opening {output} file)
added AMD optimization filter via external tool "r.js"
added unit test for "requirejs" filter
made "requirejs_config" parameter optional
allows compass output_style config option to be overridable