Issue #253: Fix failing admin menu tests.
Merge pull request #304 from quicksketch/fix-admin-menu

Issue #253: Fix failing admin menu tests.
Issue #1174640 by Niklas Fiekas, aspilicious, ericduran, cosmicdreams, amateescu, tim.plunkett: Added new HTML5 FAPI element: number.
Issue #1174646 by aspilicious, ericduran, Niklas Fiekas: Added new HTML5 FAPI element: range.
Issue #1519720 by Niklas Fiekas: Remove element_validate_integer() and element_validate_integer_positive() in favor of the new number element type.
Issue #1519852 by Niklas Fiekas: Use the new number FAPI element for the number field textfield widget.
Issue #1527988 by Niklas Fiekas: Fixed Missing or legacy number validation.