Restoring .travis.yml file for convienence until Github Actions are integrated, but not restoring the requirement that they pass (due to throttled Travis runs) for PR's to be merged.
Restoring .travis.yml file for convienence until Github Actions are integrated, but not restoring the requirement that they pass (due to throttled Travis runs) for PR's to be merged.

Unidata/netcdf-c,Unidata/netcdf-c,Unidata/netcdf-c,Unidata/netcdf-c