Add basic release pipeline

[wagoodman]

Adds a release process:

• Add release pipeline that publishes release artifacts on git tag pushed to master (also make release make target). Note: this only continues when all static analysis, unit, and integration have already run for the given tagged commit SHA.
• Adds publishing to a homebrew tap (anchore/homebrew-vulnscan)

This PR also achieves the following:

• Removes dependency on CGO (replaces go-rpmdb with a fork)
• Moves all forms of tests (except unit) under the /test dir

Todo:

• The final release process skips all publishing for the meantime, we will turn this on closer to release and after renaming the tool.
• Uploading the VERSION file to an S3 bucket will be completed in another ticket
• No acceptance tests have been added, first the DB release pipeline needs to be created.