TRUNK-3952: Enable openmrs:require tag attribute value expressions
(cherry picked from commit 86d872ee7cf211d57295505cf008e5f61eb78ce8)
Program state change displays wrong date in IE8 TRUNK-3482
(cherry picked from commit 6d2df202326977c1ad3e19be4f59ece57f12b2a8)
TRUNK-3904: Concept(Integer) constructer doesn't call this()
TRUNK-3142: Made isValid to be more permissive