Make QV4::RegExpObject header independent from masm headers

Also remove pointless uint32_t for uint values and replace
a few inconsistent uint16_t uses with quint16. MSVC was using uintN_t
defined in masm headers instead of cstdint, so this change eliminates
such situation.

Change-Id: Ibd7dd50fc047dcdc78e057299883311a24dd3960
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>