[Maxima] log(x^2) -> 2 log(x)

[John Lapeyre]

> >>  (%i1) log(x^2)
> >>  (%o1)  2 log(x)

By the way, in case it seems like its not a big deal:

A casual user should be able to do this

    n_integrate(log((1-x)^2),[x,0,2]);

without futzing around in the manual to try to find out why the integration
failed. (I am assuming the routine can handle the singularities).