Enabling > SSE 2 support for default python installation while keeping compatibility with M1

[agoscinski]

From the conversation in PR #403

Should we add march at least to the default pip installation?

librascal/setup.py

Line 31 in 9a9fbdc

cmake_args=[

Since march seems to potentially give speed ups for numerical code by enabling SSE 2 > instructions.
https://stackoverflow.com/a/52660117

Originally posted by @agoscinski in #403 (comment)

No, because this would also fail when compiling the python binding on M1 CPU.
If someone wants to put in the time to figure out a robust way to add back -march=native without breaking some platforms, we can do it later, but I would rather have something which works for now.

Originally posted by @Luthaf in #403 (comment)