Merge RBRenameTemporaryVariableTransformation and RBRenameTemporaryVariableRefactoring

[Ducasse]

Since the refactoring version does the same and its implementation has been revisited. In addition there is not breakingChanges precondition. So ignoring them is not possible so it makes the transformation useless.

[Ducasse]

@balsa-sarenac what do you think? I checked both implementations.

[Ducasse]

I will try to get the variable API because the transformation is asking for a variable while the refactoring an interval.

[balsa-sarenac]

I agree. We can kill transformation and unify apis (maybe give both interval and variable). If I remember correctly, transformation accepts variable and then searches for it?