Support for subtracting two `Tm`s, yielding a Duration.
Support for subtracting two `Tm`s, yielding a Duration.

I release this patch under the MIT license.

compressed/time,DiamondLovesYou/time,golddranks/time,vvuk/time,mark-buer/time,seanmonstar/time,pwoolcoc/time,seanmonstar/time,PeterReid/time