Remove libgreen support.
Make 'mach doc' not fail when components/servo/target doesn’t exist.
Fix 'mach browse-doc' to use the right target directory.
Update web-platform-tests.
auto merge of #4202 : zwarich/servo/remove-libgreen, r=larsbergstrom
auto merge of #4205 : servo/servo/wpt_20141202, r=jdm
Update skia submodule to get android build fix.
auto merge of #4203 : SimonSapin/servo/refactor-doc, r=Manishearth
auto merge of #4210 : glennw/servo/skia-android-update, r=metajack
Implemeneted ModifyAttribute handler to update DOM elements.
auto merge of #4214 : jdm/servo/modifyattr, r=jdm

Rebased from #4197.
Merge branch 'master' of github.com:servo/servo