Allow user to split clips at playhead while In/Out is active on multitrack

Once you set the in/out for your multitrack you cannot use the Split commands on a track in the expected way. You must remove your in/out OR you can "split" whatever is contained between the in/out points.

Often, I want to set my in/out points and not think about them again. Currently I need to clear my In/Out points, make my track changes, then re-apply the in/out points, then mixdown.  This change would let me set in/out and leave it.

Allow Split and Split All Clips under Playhead on clips contained by active In/Out points in multitrack.