JSF Validation Message Updates

This fix was submitted by Kyle Stiemann. Since validation messages no longer rely on the *Liferay Faces Portal* tag `liferay-ui:message`, I moved the section to a more appropriate spot. These edits are for the old Dev Guide.

I've updated the tutorial for LDN (in review: [LRDOCS-1216](https://issues.liferay.com/browse/LRDOCS-1216)) with this new info, which can be found on my branch [here](https://github.com/codyhoag/liferay-docs/blob/jsf-edits/develop/tutorials/articles/liferay-faces/giving-feedback-to-users-with-validation-messages.markdown).