ISIS-486, ISIS-624, ISIS-625, ISIS-626: modal dialogs, @Digits, MMV error handling

ISIS-486: improvements to modal dialog
- now correctly displays feedback error on conversion exception when tab out
- to reduce flicker, waits 250ms before performing veil transition

ISIS-624: removed @Decimal, replaced with @Digits (bringing in JSR-349 beanval 1.1 dependency)

ISIS-625: New MmvErrorPage to display any detected metamodel validation errors

ISIS-626: Built-in ExceptionRecognizer implementation for PagedExpiredException.
ISIS-486: further tweak on the modal dialog animations.
ISIS-627: fix for deleting lazily-loaded pojos