Use docker-java 0.10.3-SNAPSHOT

Since 0.10.2, DockerClientBuilder ignores empty version strings, so
there is no more need to handle this case here.
Another change is that docker-java now uses ServiceLoader internally to
locate its implementation, which fails with the default classloader.
Minor refactorings in PortBindingParser related code
Parser for bind mount definitions
UI for entering bind mount definitions