v2.9.0 - Check & Verify

Add fallback to core-instance enforcing logical changes to the active list #285.

A new mechanism to check incoming changes that could prevent undoing. This step allows more accurate calculations and contains errors to one process instead of the old approach which is led to cascading the errors.

Verify positions before confirming operation final transition #288.

Additional functionality check that's done before confirming the final transformation. Comparing the minimum - one value from the active list in the DFlex Store with the actual position as it's painting in the browser.

Prevent unnecessary re-assigning position index #287.

Miniro change restricts access to the core-instance when it's not necessary.