allow properties to be overriden from command line

I want to run multiple KCL consumers in docker. In order to have multple KCL consumer client, I need each of them using different application name with same stream. However, I am unable to set application name from command line, and that means I will need to have multiple properties file, one for each consumer to have different application name.

This is a problem for me because I will then have to know how many consumer I need to run before hand, or I will need to rebuild docker image to have more properties file with different application name. Obviously there are ways to get around these problem, but they are a pain in the ass. The best way is to allow overriding of properties attribute from command line. Thanks.