add the welcome page.
Merge branch 'master' of https://github.com/nicolasfavier/GAE-JS-AJAX

Conflicts:
	war/WEB-INF/classes/.gitignore
	war/WEB-INF/classes/models/Trainning$Kind.class
	war/WEB-INF/classes/models/Trainning.class
	war/WEB-INF/classes/servlet/communication/TrainningServlet.class
Add trainningDao
Merge branch 'master' of https://github.com/nicolasfavier/GAE-JS-AJAX