Manual setup toolchain

qbs detect-toolchains

adds toolchains to the qbs config, but it detects only toolchains which are in PATH. If I have 2 Qt version, build with different versions of MinGW/GCC, I can not easily set up the two compilers in terminal. In Qt Creator, I have set up both Qt versions and both compilers, so I have 2 different kits. Creator sets the qtc_ qbs profiles correctly for both Qt versions and compilers, it would be good if I could do the same in terminal (like it is possible to set up multiple Qt versions with setup-qt). something like:

qbs toolchain c:/mingw/4.7/bin/g++.exe mingw-47

qbs toolchain c:/mingw/4.8/bin/g++.exe mingw-48