[WIP] subroutines for analytic/parallel q-EOM calculations

[mariomotta]

Summary

Details and comments

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2 out of 3 committers have signed the CLA.

✅ manoelmarques
✅ pbark
❌ Mario Motta Mario.Motta@ibm.com

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[pbark]

@mariomotta thanks a lot for the PR and all the work done here. The test needs to be worked out a bit and there is still the discussion about the directories. Thus I rename the PR to work in progress and we can keep working in this.

[woodsp-ibm]

This work needs to be moved/resumed/finished in qiskit-nature. I created an issue there to reference this for now qiskit-community/qiskit-nature#39 Once the work has been transferred across this PR should simply be closed, but I will leave it open for now while the transfer is pending.

[woodsp-ibm]

Aqua will shortly be deprecated so I am closing this. This work should be moved/completed to qiskit-nature where I already opened an issue to track this qiskit-community/qiskit-nature#39