Add go-flags

README.md

@@ -431,6 +431,7 @@ See [go-hardware](https://github.com/rakyll/go-hardware) for a comprehensive lis
 
 * [autoflags](https://github.com/artyom/autoflags) - Go package to automatically define command line flags from struct fields.
 * [browscap_go](https://github.com/fromYukki/browscap_go) - GoLang Library for [Browser Capabilities Project](http://browscap.org/).
+* [go-flags](https://github.com/jessevdk/go-flags) - go command line option parser
 * [go-multierror](https://github.com/hashicorp/go-multierror) - A Go (golang) package for representing a list of errors as a single error.
 * [gopsutil](https://github.com/shirou/gopsutil) - A cross-platform library for retrieving process and system utilization(CPU, Memory, Disks, etc).
 * [jobs](https://github.com/albrow/jobs) - A persistent and flexible background jobs library.