Revert 'go get' command to use gemalto instead of thalesgroup

The go.mod file defines the module as github.com/gemalto/helm-spray. Changing Go module names without making breaking changes is not supported (yet). Therefore revert to use github.com/gemalto/helm-spray, as that automatically redirects to the correct git repository.

README.md

@@ -182,11 +182,11 @@ First, set up your environment:
 - If you don't have [Glide](http://glide.sh) installed, this will install it into
   `$GOPATH/bin` for you.
 
-Clone this repo into your `$GOPATH`. You can use `go get -d github.com/thalesgroup/helm-spray`
+Clone this repo into your `$GOPATH`. You can use `go get -d github.com/gemalto/helm-spray`
 for that.
 
 ```
-$ cd $GOPATH/src/github.com/thalesgroup/helm-spray
+$ cd $GOPATH/src/github.com/gemalto/helm-spray
 $ make dist_linux
 $ helm plugin install .
 ```