Merge pull request #194 from tonytheodore/qt5-wrapper

Add Qt5 convenience target
package qwt: use qt5 qmake for test program
Merge branch 'master' of github.com:mxe/mxe
Makefile: add target loop, serialise targets, and update settings file
add mingw-w64 runtime and pthreads implementation, update related toolchain files
various packages: enable/disable mingw-w64 builds
Merge branch 'mingw-w64' into multi-rebase
package qt: remove mac arch/ssse3 patch
raise deprecation error after merge into mxe master