Classical Control rewrite support should be refactored

[swernli]

https://github.com/microsoft/qsharp-runtime/blob/main/src/Simulation/QSharpFoundation/ClassicalControl.qs defines the Q# operations used in our classically controlled rewrite step (see https://github.com/microsoft/qsharp-compiler/blob/main/src/QsCompiler/Transformations/ClassicallyControlled.cs). As mentioned in a comment on the qs file, the namespace name is out of date and should be updated, along with other clean-up and refactoring to allow it to be used correctly by the rewrite step without needing to be exposed publicly. This refactor will need to take several steps:

• Minimize number of intrinsics in ClassicalControl.qs to reduce load on implementers (Updating ClassicalControls to reduce intrinsics #529)
• Update generated code for concrete intrinsics that use interfaces to not be gate specific. (Update concrete intrinsic naming conventions #538)
• Rename namespace, updating qsharp-compiler rewrite step with new name. (Introduce ClassicalControl namespace, depreicate old namespace #692, Updating ClassicalControl rewrite to use new namespace qsharp-compiler#1037)
• Switch Q# foundation to use interfaces for intrinsic implementation. not required for rename.
• Change remaining callables in ClassicalControl.qs to be internal. control callables will not be internal.
• Change all non-intrinsic callables in ClassicalControl.qs to be internal. (Make non-intrinsic ClassicalControl callables internal #535) control callables will not be internal.