Extract ordered list of meter pairs from components.
Example:
abjad> t = Staff([RigidMeasure((2, 8), construct.scale(2)),
RigidMeasure((3, 8), construct.scale(3)),
RigidMeasure((4, 8), construct.scale(4))])
abjad> metertools.extract_meter_list(t[:])
[(2, 8), (3, 8), (4, 8)]
Useful as input to some rhythmic transforms.