Add support for MacOSX x86_64
(cherry picked from commit 1307f0949c9b6e1ef2e8a3128c2113bbd7f17a58)
Add extension description

(cherry picked from commit a738920303e77022fa89740c16cb832ee3477fa2)

Conflicts:
	odk/examples/cpp/complextoolbarcontrols/Makefile

Change-Id: I28af30dc04068c670d31be7494b7ce9a7a25c3a3