tweak to make clearer some implicit dependencies (#68)

Signed-off-by: Jordan Keister <[email protected]>

Signed-off-by: Jordan Keister <[email protected]>

docs/tutorial.md

@@ -44,7 +44,7 @@ Use the [Operator SDK](https://sdk.operatorframework.io/docs/installation/) CLI
 Create a directory for the memcached operator:
 
 ```
-mkdir -p <directory>
+mkdir -p memcached-operator
 ```
 
 Navigate into the newly created directory and initialize the project with:
@@ -84,6 +84,8 @@ The following command will build and push an operator image:
 make docker-build docker-push IMG=<registry>/<user>/<img-name>:<version>
 ```
 
+Note:  this tutorial will use the docker image tag `example.com/memcached-operator:v0.0.1` for future steps.  You should replace references to this with the docker tag you pushed as `IMG`, above.
+
 ### Generating CRD manifests 
 
 ```sh