[skip AppVeyor]
Fixes#4196 but may trigger #3611, this is a test build
intented to help on release version selection.
Upgrade Python AppImage to 3.7.13 since 3.7.12 is no longer available.
[publish binaries]
[skip appveyor]
Not a great difference, but we are too close to 50' limit
Also reduce curl max time to avoid timouts.
For Linux buils remove --silent build to avoid the job being cancelled
Existing code for OSX was migrated to scripts on travis/osx without changes.
New scrtps for Linux were added to travis/linux based on previous work
by gcoco and LyzardKing
Install linux dependencies similar to OSX version, including samplerate,
vlc, ical, kml, d2xx, srmio, libusb-compat/libusb1.0 and R 3.5
Enable CloudDB and Cloud services using shared secrets with OSX version
Generate AppImage and set src/$FINAL_NAME to enable automatic deploy
Optionally upload the AppImage to transfer.sh for testing
