Bugfix for cooling call... Also want to test using mue functionality.

[nfrontiere]

A bug is in the call to the cooling function:

In all instances where m_radcool is called
i.e.
RAD_T lambda = (*m_radcool)(Ti, (RAD_T)rhoi, (RAD_T)Zi, (RAD_T)Yi, (RAD_T)aa_av, mui, &iter, false, &nHIi, &nei);

You need to call it with the metalicity-free (or primordial) Y not the true value of Y.

Meaning if the particle data has a value of Yi
you need to calculate:
double y = Yi/Xi;//nHe/nH * (mHe/mH)
double Yp = y/(1.0+y);//Metal-free helium fraction
and use Yp, instead of Yi in the m_radcool call

Also m_radcool now returns mu_e
so instead of doing nemass/rho to get neV = Ne
you can just use mass/mu_e*mh = Ne
Perhaps is the same but avoids worry about density. I think in general though using mi/rho for volume is consistent too

[nfrontiere]

reminder for later that our Cloudy tables now have the ability to measure L instead of using free-free emission approximation only. need to update the map codes to use it