Expand "collect and combine like terms" to be more general (multiplication) about mathsteps

[evykassirer]

Hmmmm so related to the conflict with #45...

This would also be helpful for a problem like (x-3)*5*(x-3) / (x-3)^2

Because it would collect the (x-3)s on top first -> (x-3)^2*5 / (x-3)^2 and could cancel out, instead of multiplying out the whole top and bottom of the fraction first

But x-3 can't be simplified. So this would only happen if cancelling out is possible!

I'm confusing myself a bit around this. So if you want to take this on, let's chat!