Run go get as part of containerized version

[lizrice]

Nice tool!

I'm looking at the containerized version and I'd like to add a step to do go get (to get the dependencies installed into the file system on the container). A very little local testing suggests this could be achieved by adding go get ./... just before the exec line in entrypoint.sh.

Happy to do a PR but I thought I'd run the idea past you first. Wdyt?