Add glide-pin plugin
Adds a link to the glide-pin plugin for pinning all discovered dependencies in the `glide.lock` file explicitly in the `glide.yaml` file. Respects version ranges, but will replace them if the `--exact` flag is used.
diff --git a/docs/plugins.md b/docs/plugins.md
index 4983b95..367de5f 100644
--- a/docs/plugins.md
+++ b/docs/plugins.md
@@ -10,6 +10,7 @@
* [glide-brew](https://github.com/heewa/glide-brew) - Convert Go deps managed by glide to Homebrew resources to help you make brew formulas for you Go programs.
* [glide-hash](https://github.com/mattfarina/glide-hash) - Generates a hash of the `glide.yaml` file compatible with Glides internal hash.
* [glide-cleanup](https://github.com/ngdinhtoan/glide-cleanup) - Removing unused packages from the `glide.yaml` file.
+* [glide-pin](https://github.com/multiplay/glide-pin) - Take all dependencies from the `glide.lock` and pin them explicitly in the `glide.yaml` file.
_Note, to add plugins to this list please create a pull request._
