Restore form validation error message removed in deformdemo test fixes

772b8ce8664cb03f1fb2c893175c47a75a496f7c#diff-67b2f092186b770c5b490505b61462c5

Conflicts:
	deform/templates/form.pt
Fix i18n msg id typo.  I swear I copied and pasted this.  :-)
Resolve merge conflict.