Remove the external dependencies from the repo

This has only caused issues with other clones as they can't get the
dependencies as the directories exist and "go get" craps out. Will be
adding these to .gitignore and updating setup scripts to install them if
they aren't there yet.
Change my dependencies into a git submodule
Also go get update the assert package
Document how to add a dependency to the app
Fix fps mapping test to match hard-coded sensitivity values