fix #22131: bad diatonic transposition of Cb, Cbb
add back gesture to zoom in/out
add QGestureEvent to precompiled header
remove precompiled header for Mingw :( see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56926
Make some strings translatable
Merge pull request #595 from Jojo-Schmitz/translate_fotomode

Make some strings translatable
also B#, B## - and add test

transpose tests were not being run, it seems, but they do work, so I am
enabling them and adding a diatonic transpose test that includes a full
chromatic scale.
Merge pull request #596 from MarcSabatella/22131-transpose-cb

fix #22131: bad diatonic transposition of Cb, Cbb