Release 4.1.4

• Contains and some other functions would modify the input values in place to save a little on memory allocations. But this is surprising behavior in many cases, and wasn't always even controllable by the caller. All functions now make copies of the input values and normalize the copies, leaving the input value untouched. This is safer in most cases. Callers can normalize the value first before calling the other functions, to avoid the allocations, if necessary.