vdk config-help prints all configs in lower-case so it's easy to copy
paste it and set it and it's error prone to allow only upper-cased.
Spring does the same thing when inferring applicaiton properties from
environment variables.

Added also better testing around use-cases with configuration in the
functional test suite

Testing Done: the functional tests

Signed-off-by: Antoni Ivanov <aivanov@vmware.com>