Updates for CI#1760

Merged

0xc0170 merged 10 commits intoARMmbed:masterfrom

sg-:master

May 27, 2016

Commits on May 9, 2016

Commits on May 23, 2016

remove default path to GCC. Setting takes priority to PATH so this breaks linux and Mac
sg-
committed

Commits on May 24, 2016

revert is_supported chages in favor of alternative command line option
sg-
committed