Implement logging/warning functionality to be able to change verbosity

[dhuppenkothen]

X-PSI prints a lot of stuff to stdout, which is challenging in applications where we might need to reinstantiate the likelihood multiple times.

It'd be good to implement a proper logging scheme such that the user has some control about when things are printed to the screen.

[thjsal]

As far as I see, there is a function for verbosity control here:

xpsi/xpsi/utils.py

Line 9 in 4febad2

def make_verbose(enter_msg='', exit_msg=''):

But seems to me that the options deactivate_verbosity and deactivate_all_verbosity are not working at the moment.