Support CMake toolchain for Android and iOS

There's been various conversations on blog post comments, mailing lists and the forums to suggest there are people who want the ability to build Qt projects for Android and iOS using CMake. Which makes sense since this is a valid choice for desktop applications. I see a number of issues closed suggesting this is out of scope but I'd like to raise this as a suggestion so the community can at least vote/watch the issue.

http://qt-project.org/forums/viewthread/36359
http://stackoverflow.com/questions/9871337/cmake-fails-to-find-qtcore-library-when-crosscompiling
http://lists.qt-project.org/pipermail/android-development/2013-May/000104.html
http://blog.qt.digia.com/blog/2013/07/03/qt-5-1-released/#comment-947852
https://qt-project.org/forums/viewthread/35836