Issue 9357 & Issue 6833 - Printing float literals should be done with a franctional part

http://d.puremagic.com/issues/show_bug.cgi?id=9357
http://d.puremagic.com/issues/show_bug.cgi?id=6833

I would still like to print only 1 or 2 digits in the fractional part, but I can't figure out how to do that with `sprintf`.