ability to create project from jar with project context

[hohwille]

For Java projects we already support local maven projects where the POM is read, dependencies are resolved, etc.
The same should also be possible for a JAR artifact as maven puts the POM by some convention into the JAR file. So if we can find the POM in the specified JAR then also dependencies from that POM could be honored, sources could be retrieved from the maven repo, etc.