check for structure equivalency not identity

src/mol-canvas3d/canvas3d.ts

src/mol-plugin/state/animation/manager.ts

src/mol-repr/structure/complex-visual.ts

src/mol-repr/structure/units-visual.ts

src/mol-repr/structure/visual/carbohydrate-link-cylinder.ts

src/mol-repr/structure/visual/carbohydrate-symbol-mesh.ts

...r/structure/visual/carbohydrate-terminal-link-cylinder.ts

...ol-repr/structure/visual/cross-link-restraint-cylinder.ts

src/mol-repr/structure/visual/inter-unit-link-cylinder.ts

src/mol-repr/structure/visual/intra-unit-link-cylinder.ts

src/mol-repr/structure/visual/util/element.ts

src/mol-repr/structure/visual/util/nucleotide.ts

src/mol-repr/structure/visual/util/polymer.ts