Go Compiler Version

Currently, the building docker process fails with this error :
```
Go version 1.1.x (or higher) required, you have a version of go that is too old See http://golang.org/doc/install for upgrading.
Makefile:23: recipe for target 'go-check' failed
make: *** [go-check] Error 1
```

After a bit of fiddling, I chose to add a `git checkout v0.3.1` tag to bypass this.

Therefore I thout it could be good to merge it back. :p