Moves the existing points-to predicates to the newly added class
`ControlFlowNodeWithPointsTo` which resides in the `LegacyPointsTo`
module.
(Existing code that uses these predicates should import this module, and
references to `ControlFlowNode` should be changed to
`ControlFlowNodeWithPointsTo`.)
Also updates all existing points-to based code to do just this.
How could the tests fail because of autoformatting, you may ask?
The answer is deprecation warnings. These specify the location of the deprecated
entity, and due to autoformatting these moved around.