Integrates spf13/cobra for command handling.
Adds some path helper functions.
Replaces a custom FindCWD function with the simpler os.Getwd(). OK for now.
Sets up rudimentary muxing for the various features of the app:
/api is being served by a JSON api HandleFunc
/admin is being routed to a FileServer directory where an AngularJS application will live.
/ is being routed to a FileServer directory where compiled HTML will theoretically live.