Allow process timeouts to be specified for Yui

- provide a setTimeout method to specify the timeout that the process can run for (currently hardcoded to 60 seconds)
- provide a means that this can be applied to other filters which use the ProcessBuilder
Merge remote branch 'upstream/master'
added missing test group
Merge pull request #277 from steveybaby2/master

[Filters] Fixed issue with Yui process timing out by providing a setTimeout function
add setter for http_fonts_path
added ProcessFilter::createProcessBuilder()
renamed abstract class per standards
marked broken test as incomplete
Add .gitattributes
do not exclude the readme and the changelog
Merge pull request #347 from carlosbuenosvinos/master

Make Assetic a Composer "light-weight-distribution-package"
added BaseNodeFilter

renamed some private vars
added some default values
updated uglifyjs filter to use --no-mangle

This is necessary in order for UglifyJS 1.3.4 to
work since the --mangle option doesn't appear to
exist. If there are earlier versions of UglifyJS
that don't have the --no-mangle option we will
need to figure out compatibility for both.
made integration tests smarter
Merge remote-tracking branch 'uwej711/support_http_fonts_path'
made compass test smarter
added a skip for incorrect uglifyjs version
added UglifyJs2Filter
updated changelog
added --verbose flag to travis config