Improve JavaDocs
Export californium package in order to provide access to
CaliforniumBasedRequestHandler from other OSGi bundles
Remove CDN. Add dependencies(js, css) in "vendor" directory.
Use Jetty's EventSourceServlet for pushing notifications to web UI
Merge remote-tracking branch 'origin/master' into observe

Conflicts:
	leshan-standalone/src/main/resources/webapp/index.html
pom file cleanup
Merge remote-tracking branch 'origin/master' into observe