Change python module name for simultaneous compatibility with CLASS

[carlosggarcia]

I normally have to work with both CLASS and hi_class. Although hi_class is an implementation on top of CLASS, the versions of CLASS roll faster than those of hi_class, so CLASS bugs can be still present on hi_class. More importantly, I might want to keep running one LCDM MCMC and launch a MG one (which might involve go to a new branch y recompile the code). However, I think that recompiling hi_class can potentially create some problems with the LCDM run.

What would you think of changing the value of the python module to hiclassy or something like that, so that one can have both codes installed at the same time?

[IamSreeman]

Maybe you can install both on 2 different conda environments? @miguelzuma