177-qFit to work for EM with appropriate SF

[stephaniewankowicz]

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This is a significant change to how we handle EM maps.

1. We are now using electron SF. The electron SF is only 5 'rings' while X-ray is 6. Therefore in the transformer code, we now flag if it is EM which changes some of the calculations.
2. We got rid of scattering as this is now folded into EM
3. With EM, we have a base cardinality of 3 rather than 5.
4. We remove the bulk solvent masking as done in X-ray as most EM maps do not have a 'bulk solvent' region. This may change in the future.

There will likely need to be updated over the next 2 years as more details and metrics emerge about how EM maps are handled.

Description of the Change

Release Notes

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