fix typo in README.md

s/filling/filing

README.md

@@ -203,7 +203,7 @@ Redeploy your application to have your changes applied, and open the welcome pag
 
 ## Looking for help
 
-If you get stuck at some point, or think that this document needs further details or clarification, you can give feedback and look for help using the channels mentioned in [the OpenShift Origin repo](https://github.com/openshift/origin), or by filling an issue.
+If you get stuck at some point, or think that this document needs further details or clarification, you can give feedback and look for help using the channels mentioned in [the OpenShift Origin repo](https://github.com/openshift/origin), or by filing an issue.
 
 
 ## License