Declarations - const enum to enums

[RaananW]

When preserving const enums (to be available in js) the exported code is identical to a standard export ofr an enum. However, typescript still fails compilation when trying to iterate over it though it will work correctly when used directly in js.

This reverts const enums to enums in our UMD declarations, which will allow any playground using enum iteration in typescript to work.

[bjsplat]

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[bjsplat]

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[bjsplat]

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[bjsplat]

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