This will allow the command to update the package if an old one happens to be present while still fetching it if it's missing. Suggested by @shurcooL in #28.
@@ -33,7 +33,7 @@ http://localhost:6060/pkg/github.com/davecgh/go-spew/spew
## Installation
```bash
-$ go get github.com/davecgh/go-spew/spew
+$ go get -u github.com/davecgh/go-spew/spew
```
## Quick Start