Waveform operation between waveforms with different dimensions should be possible

[henjo]

Waveform operation between waveforms with different dimensions should be possible.

Example

w1 is a 3x4x5 waveform
w2 is 3x4 waveform

w1-w2 should produce a 3x4x5 result

[henjo]

Basically Waveform objects should handle broadcasting like numpy arrays