Add CLI spinner util

README.md

@@ -513,6 +513,7 @@ Please take a quick gander at the [contribution guidelines](https://github.com/a
 * [okrun](https://github.com/xta/okrun) - go run error steamroller
 * [peco](https://github.com/peco/peco) - Simplistic interactive filtering tool
 * [profile](https://github.com/davecheney/profile) - Simple profiling support package for Go
+* [spinner](https://github.com/briandowns/spinner) - Go package to easily provide a terminal spinner with options.
 * [sqlx](https://github.com/jmoiron/sqlx) - provides a set of extensions on top of the excellent built-in database/sql package
 * [xlsx](https://github.com/tealeg/xlsx) - Library to simplify reading the XML format used by recent version of Microsoft Excel in Go programs.