Issue #1541838 by ericduran, Dave Reid: Backported number and range field changes and validation.
Issue #1942050: Added support for pattern attributes.
Issue #1330024: Added placeholder support for password core elements.
Added validation callbacks for email and url elements.
Initial horizontal tabs commit from fieldgroup code.
Stripping CVS keywords
by Dave Reid: Updated for #954804.
by Dave Reid: Backported improvements from Drupal 7 port.
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