Add interactive matplotlib selector to `PolygonPixelRegion`#406

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dhomeier wants to merge 3 commits intoastropy:mainfrom dhomeier:polygon-selectors

+149-9

Commits on Dec 8, 2021

Add as_mpl_selector and centroid to PolygonPixelRegion
dhomeier
committed

Commits on Dec 23, 2021

Update selector to new API and verts.setter
dhomeier
committed

Commits on Dec 30, 2021

Experimental rotation.setter for PolygonPixelRegion
dhomeier
committed