Added some steps when provisioning 'lorne' VM:

Hi, 

I created some steps on Vagrantfile to help when using 'go get .. '  and 'go install ..' inside VM 

See them bellow : 

 * Create subdirectories {src, bin, pḱg} under $GOPATH directory
  * Export $GOPATH/bin to $PATH.  
  * Install git and mercurial packages.