New angle sampling causing too many conformers

[stephaniewankowicz]

Now that we are sampling the angle at 360 degrees, we are creating too many conformers for almost all aromatic residues.

Testing two options:

1. putting QP step at the end of angle sampling
2. creating remove conformers below cutoff (see: Test & improve metrics for removing low density conformations #346)

[stephaniewankowicz]

I test removing low density conformers and putting a qp test in angle. Both removed almost all of the 'too many conformers, reverting'. However, the qp in angle kinda blew up the R-free while the remove conformer even if one atom is below a certain threshold tended to increase the number of residues where we could not find a solution. I am going to close this PR as we should not implement a qp set in angle but will continue the conversation/testing in #346