Add gvt to package management. (#1017)

README.md

@@ -697,6 +697,7 @@ See [go-hardware](https://github.com/rakyll/go-hardware) for a comprehensive lis
 * [gopm](https://github.com/gpmgo/gopm) - Go Package Manager
 * [govendor](https://github.com/kardianos/govendor) - Go Package Manager. Go vendor tool that works with the standard vendor file.
 * [gpm](https://github.com/pote/gpm) - Barebones dependency manager for Go.
+* [gvt](https://github.com/FiloSottile/gvt) - `gvt` is a simple vendoring tool made for Go native vendoring (aka GO15VENDOREXPERIMENT), based on gb-vendor.
 * [johnny-deps](https://github.com/VividCortex/johnny-deps) - Minimal dependency version using Git
 * [nut](https://github.com/jingweno/nut) - Vendor Go dependencies
 * [VenGO](https://github.com/DamnWidget/VenGO) - create and manage exportable isolated go virtual environments