std.rational -- update and progress towards review

[Joseph Rushton Wakeling]

On 04/10/13 21:43, Walter Bright wrote:
> On 10/4/2013 12:31 PM, Joseph Rushton Wakeling wrote:
>> It is 95% -- I can always see if I can improve that :-)

It's now 98% :-)

It'd be 99% if these two expressions were each placed on one line instead of 
wrapped, but I figure that would be greedy:
https://github.com/WebDrake/phobos/blob/rational/std/rational.d#L827-L830

Apart from that there's one line that is not an assert(0) that is not covered, 
which I guess just comes down to it being very rare that it should be activated:
https://github.com/WebDrake/phobos/blob/rational/std/rational.d#L593