Merge remote-tracking branch 'upstream/master' into wx3

Makefile.in

images/Cursors.h

mac/Audacity.xcodeproj/project.pbxproj

plug-ins/SpectralEditMulti.ny

plug-ins/SpectralEditParametricEQ.ny

plug-ins/SpectralEditShelves.ny

src/Audacity.h

src/AudacityApp.cpp

src/AudioIO.cpp

src/AudioIO.h

src/AutoRecovery.cpp

src/BatchCommands.cpp

src/BlockFile.cpp

src/BlockFile.h

src/Dependencies.cpp

src/Dependencies.h

src/DirManager.cpp

src/DirManager.h

src/Envelope.cpp

src/Envelope.h