[TASK] Add Elitism with diversity preservation to NSGA-II

[Jimmy-INL]

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Issue Description

Adding some sort of Elitism algorithms to NSGA-II will significantly boost the performance
Is your feature request related to a problem? Please describe.
This will keep the elitist individuals so even if we removed duplicants you still have the fit individuals. It's strongly recommended to add some preservation of diversity as well.

Describe the solution you'd like
There should be a user-input like keepElitist = True in the survivor selection for instance. This invokes that option.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.
It can be an enforced loop in the code which will no longer be optional.

For Change Control Board: Issue Review

This review should occur before any development is performed as a response to this issue.

• 1. Is it tagged with a type: defect or task?
• 2. Is it tagged with a priority: critical, normal or minor?
• 3. If it will impact requirements or requirements tests, is it tagged with requirements?
• 4. If it is a defect, can it cause wrong results for users? If so an email needs to be sent to the users.
• 5. Is a rationale provided? (Such as explaining why the improvement is needed or why current code is wrong.)

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For Change Control Board: Issue Closure

This review should occur when the issue is imminently going to be closed.

• 1. If the issue is a defect, is the defect fixed?
• 2. If the issue is a defect, is the defect tested for in the regression test system? (If not explain why not.)
• 3. If the issue can impact users, has an email to the users group been written (the email should specify if the defect impacts stable or master)?
• 4. If the issue is a defect, does it impact the latest release branch? If yes, is there any issue tagged with release (create if needed)?
• 5. If the issue is being closed without a pull request, has an explanation of why it is being closed been provided?