Simulation Performance Improvements

[alexanderbez]

Disabling the distribution CanWithdrawInvariant invariant speeds up simulation noticeably.

/cc @jaekwon

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• Targeted PR against correct branch (see CONTRIBUTING.md)

• Linked to github-issue with discussion and accepted design OR link to spec that describes this work.

• Wrote tests

• Updated relevant documentation (docs/)

• Added entries in PENDING.md with issue #

• rereviewed Files changed in the github PR explorer

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For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #3818 into develop will decrease coverage by 0.01%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop    #3818      +/-   ##
===========================================
- Coverage    60.86%   60.84%   -0.02%     
===========================================
  Files          192      192              
  Lines        14288    14288              
===========================================
- Hits          8696     8694       -2     
- Misses        5025     5027       +2     
  Partials       567      567

[jackzampolin]

This is a great one!