Patch for bug #53 on version 0.5.0

This is a patch that we have utilized at IDEXX Labs for the the bug described above.
We have tested and verified this on x86 32 and 64 bit linux and 32 bit arm.
Merge pull request #21 from hiharin/master

Hmmm. Not ideal. A round-trip should reproduce the original, but null -> NaN -> ? But I guess it's no worse than it was.

The different behavior for Win CE is troubling, but it only affects people who are using these extreme values.

I've worked with Inf/NaN before, so I understand your pain.