Improvements/Suggestions in gateway-docker

Improvements/Suggestions in gateway-docker:

• Will it be better to run gateway/ldap in background, so that we can restart the services while keeping the container running always (after config changes, log level changes etc) or should we use the current implementation (stop the container, and start it again for those changes to take effect).
• Should we run the ldap service in the same container as gateway server, otherwise we have to update the hostname in topologies to use ldap service. (Current implementation is ideal according to docker container design i.e. separate containers for specific services, but from usability point of view will this approach be better ?)
• Typo in docker dir path https://github.com/apache/knox/blob/master/gateway-docker/README.md