The maintainers messed with the v1.5.2 tag which causes Go checksum
validation problems as the Go module proxy saw and recorded the original
hash.
This updates to 1.5.3 which doesn't have the issue.
* start fixing up tests
* fix up tests + automate with drone
* fiddle with linting
* messing about with drone.yml
* some more fiddling
* hmmm
* add cache
* add vendor directory
* verbose
* ci updates
* update some little things
* update sig