use ma.log10 instead of np.log10 in interp.hght()

[ahijevyc]

Should ma.log10() be used at the end of the interp.hght() function instead of np.log10()?

return generic_interp_pres(ma.log10(p), prof.logp[::-1], prof.hght[::-1])

I would like to avoid the log10 of zero warning, but don't want to break anything. I tried a pull request, but couldn't figure out how to isolate this change from the rest of my changes.

[wblumberg]

Hi @ahijevyc

I went ahead and incorporated this change into Andover. It passed all the tests, so it doesn't look like it's going to disrupt anything! Thanks for the recommendation.

Greg