Since PR #2170, CPRadioGroup were truncated because they are specific components translated into a NSMatrix (CPView) object.
This fix sets CPRadio controlSize according to xCode value and uses its frame adjustment to adjust CPRadio inside a CPRadioGroup.
Without this fix, a matrix with a target-action pair would crash when the cib was loaded due to the matrix having been replaced with a `CPView` (which cannot take a target-action pair).
Now if the matrix is for radio buttons, the action connection for the matrix is made to the `CPRadioGroup` instead and works as expected when radio selections are made.