We did this to minimize source size and make it compile faster. Nowadays
byte slice literals compile as fast as anything, and the source isn't
checked in so it doesn't matter how big it is.
Not using base64 avoids a decode step at startup and makes the binary
about 400k smaller.
- Move the Go files into script/ instead of random places
- Rewrite check-contrib.sh into check-authors.go and check-copyright.go
- Clean up build.sh a little bit