Merge branch 'master' into windows

diff --cc libs/ardour/ardour/lv2_plugin.h
Simple merge

diff --cc libs/ardour/audio_diskstream.cc
Simple merge

diff --cc libs/ardour/lv2_plugin.cc
Simple merge

diff --cc libs/ardour/midi_track.cc
Simple merge

diff --cc libs/gtkmm2ext/motionfeedback.cc
Simple merge

diff --cc wscript
Simple merge