Fixes memory leak in netty-socketio.

* Do not include Mobile in WAR
* Deploy frontends and customization to their own contexts in dev env
* Update Connector and Jetty dependencies

This includes usage of newest connector-client. The last maven based
version 0.41.0 had been replaced by newer 0.7x version wich includes some
new features.

Removed netty dependency. It is only needed by netty-socketio and should
not be required in our POM explicitly.
Updated jackson-databind dependency to version 2.2.2.

These changes hopefully fix the threading problems with redeployment on
Tomcat 7.