Updated to use Log4J 2.x and explicitly called out the SLF4J versions so...

... they are all the same as Repose.
It can actually be removed since it is a duplicated dependency from the parent POM. In the parent, this is the only SLF4J/Log4J2 dependency that is not limited to test scope. Since they are all required for the CLI tools at runtime, the scoping had to change on the rest.