WIP: Start numeric type for resources

Opening for comments on this approach. Not functional yet.
1. I like the way this is going :-).

2. Let's put the plain SI suffixes back, please (K, M, G, T, P, E), as well as the powers of 2.
Xi should be Ei.
Apparently, Ki is indeed a thing (not ki) - but note that the SI power-of-10 equivalent is k, not K.
It turns out that binary versions aren't defined for anything less than Ki, so we don't need those: http://en.wikipedia.org/wiki/Binary_prefix