a couple changes to metab.ols; untested

I made some changes to metab.ols that could improve performance (see flux, line 22) ... assuming that my changes provide same output. I haven't tested the code that was written previously or the code that I added, but everything looks OK. Also, adjusted the output of metab.ols to take advantage of attr() for standardizing output, simplifying and condensing output appearence, yet still maintaining all of the detail and information for which one could hope (as per discussion b/w RDB and LAW). Also added NEP as output, but there are several ways to use NEP (different ways might have different, but very small, advantages).