fixed loading of linked module and lib directory into classpath

Old dev flow was:
mvn package vertx:runMod
* it builds module
* puts it in target/mods
* loads runs module from target/mods

To change something in runtime, you have to make 
mvn package
so target/mods is updated

That's very uncomfortable.

My proposed flow is
mvn package vertx:runMod

and that's it. If you change anything in verticle, just save class (I assume that you have autobuild of saved class - can be achieved in IntelliJ Idea and in Eclipse), and class goes to target/classes and vert.x picks it up.

Now vert.x first loads into classpath files pointed by module.link -> vertx_classpath.txt and then lib directory from targe/mods/yours_module. That's very important because most of people has some external dependencies that lands in lib directory.Without adding lib into classpath you cannot run your module.

If you have other questions, just catch me at bartek.zdanowski on Gmail.com