Javadoc : add mentions in the header

Forked from #874

Suggestion : Restlet Framework, version number

workload: 1h (see javadoc documentation http://docs.oracle.com/javase/7/docs/technotes/tools/windows/javadoc.html)

Assigned to JLO for roadmap priorization

[jlouvel]

Let's add it on two lines (sample values):

• Line 1: Restlet Framework 2.3 M2
• Line 2: OSGi Environments

Other sample:

• Line 1: Restlet Framework 2.2.1
• Line 2: Java Enterprise Edition

Assigned to @thboileau