Unify LONG_DESCRIPTION in setup.py and use delvewheel to repair Windows wheels

[ulupo]

I think the reason for

giotto-ph/setup.py

Lines 29 to 30 in 780f456

	if platform.system() == "Windows":
	LONG_DESCRIPTION = "giotto-ph at https://github.com/giotto-ai/giotto-ph"

(which is absent in pyflagser and giotto-tda) and for the fact that we don't include a Giotto logo here is that issues arise when building Windows wheels due to the different treatment of newline characters between Windows and Unix.

giotto-ai/pyflagser#80 fixed this in pyflagser by using a sed command we already used in giotto-tda and pyflagser Azure pipelines. I suggest we do the same here (and include a Giotto logo in the README).

Finally, also in giotto-ai/pyflagser#80 I introduced delvewheel to repair Windows wheels, and I suggest we can consider doing it here too.