Merge pull request #321 from orchardup/update-install-docs-for-0.5.1

Update install docs for 0.5.1

Author: bfirsh

docs/install.md

@@ -16,12 +16,12 @@ Docker has guides for [Ubuntu](http://docs.docker.io/en/latest/installation/ubun
 
 Next, install Fig. On OS X:
 
-    $ curl -L https://github.com/orchardup/fig/releases/download/0.5.0/darwin > /usr/local/bin/fig
+    $ curl -L https://github.com/orchardup/fig/releases/download/0.5.1/darwin > /usr/local/bin/fig
     $ chmod +x /usr/local/bin/fig
 
 On 64-bit Linux:
 
-    $ curl -L https://github.com/orchardup/fig/releases/download/0.5.0/linux > /usr/local/bin/fig
+    $ curl -L https://github.com/orchardup/fig/releases/download/0.5.1/linux > /usr/local/bin/fig
     $ chmod +x /usr/local/bin/fig
 
 Fig is also available as a Python package if you're on another platform (or if you prefer that sort of thing):