Implement basic mirror groups.#1109

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phkahler wants to merge 5 commits intosolvespace:masterfrom

phkahler:mirrorX

Commits on Sep 12, 2021

Implement basic mirror groups.
phkahler
committed

Commits on Sep 19, 2021

Fix describe screen - missing items.
phkahler
committed

Commits on Sep 26, 2021

Add one-two sided option for mirror groups
phkahler
committed

Commits on Nov 20, 2021

small changes
phkahler
committed

Commits on Dec 19, 2021

Calculate mirrored normal exprs the same way an numeric values
phkahler
committed