Add GitHub Actions to test on Ubuntu 16.04, 18.04 and 20.04, using GStreamer 1.8, 1.14 and 1.16 respectively. Fix up tests to work with only GStreamer good plugins, but add GStreamer bad plugins for 20.04 test only (currently used in time code meta test).
Add GitHub Actions to test on Ubuntu 16.04, 18.04 and 20.04, using GStreamer 1.8, 1.14 and 1.16 respectively. Fix up tests to work with only GStreamer good plugins, but add GStreamer bad plugins for 20.04 test only (currently used in time code meta test).