Automatically add h:messages if ProjectStage is Development

If ProjectStage is Development and there is no h:messages component on the current view we should automatically add h:messages to the component tree, because many users often forget about adding this useful (debug) component and wonder why their actions are never called.

This is also an official JSF 2.0 spec requirement, however I couldn't find it in the spec-pdf or in the javadoc, but in the spec issue tracker [1] and on several blogs like Ryan Lubke's Blog [2]. Furthermore Mojarra also does it.

[1] https://javaserverfaces-spec-public.dev.java.net/issues/show_bug.cgi?id=314
[2] http://blogs.sun.com/rlubke/entry/jsf_2_0_new_feature2