Publish on crates.io

needed as a dependency to https://git.ligo.org/cds/software/cr_tools/ligo_hires_gps_time

Or possibly reverse the dependency. It's convenient down-stream to have conversion to/from NDS time type and the PipInstant type from ligo_hires_gps_time. This would eliminate a feature in ligo_hires_gps_time and probably wouldn't require a feature in nds_client_rs, since ligo_hires_gps_time doesn't link to any shared libraries on its own, the dropping the nds feature would open the door to a crates.io release.