Merge branch 'master' into cairocanvas

diff --cc gtk2_ardour/ardour_ui.cc
Simple merge

diff --cc gtk2_ardour/panner_ui.cc
Simple merge

diff --cc gtk2_ardour/processor_box.cc
Simple merge

diff --cc gtk2_ardour/sfdb_ui.cc
Simple merge

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