Add hint about develop branch.

Author: jblueh

_docs_v7/Container-Development.md

@@ -37,6 +37,8 @@ The most recent versions of prebuilt container images can be found in the [GitHu
 
 In the following we give a small overview on how to use the containers to compile and run the tests. We will only cover basic commands for docker. If you are interested in learning more, check out the [official documentation](https://docs.docker.com/).
 
+Please note that some of the examples refer to features that are only available in the lasted [develop](https://github.com/su2code/SU2/tree/develop) branch of SU2.
+
 
 ## Running a container ##