This adds the OS and CC detection and cleans up the globals.h to
some degree. It also places all of the C++11 feature detection into
globals.h.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/21223003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15953 ce2b1a6d-e550-0410-aec6-3dcde31c8c00