Fixing problems with pageHiding() and IsWidget

For IsWidget pages 'pageHiding()' was called with the wrapped widget instead of the actual page.
Merge branch 'ERRAI-486-fix' of github.com:jbarop/errai into jbarop-ERRAI-486-fix

Conflicts:
	errai-navigation/src/test/java/org/jboss/errai/ui/nav/client/local/NavigationTest.java
Regression test for very long i18n strings (functionality was already working; just lacked tests)
Fixed ERRAI-611
Removed javadoc description of Service field annotations (ERRAI-289)
Fixed delivery of messages to local services on the server
Fixed ERRAI-613: Allow for special chars in file names when scanning the classpath

This is the same fix we applied to MetaDataScanner on 1/4/12. The new scanners introduced since then (translation, less, validation) didn't rely on the same functionality.
Merge branch '2.4'