==========================
ADDED:
* Support for quadrature dispatching for `Mul`, `Add` and (independent) `J`.
CHANGED:
* Refactor approximate_moment:
* Remove unused antithetic variate. (Really never used.)
* Remove redundant support for multiple exponents at once. In practice only
one is called at the time anyway.
* Adding buffering for both quadrature and results, so to reduce needed
computation for recursive methods.
* New order default: 1000 -> 1000/log2(len(dist)+1)
About the same for lower dimensions, but scales better with higher
dimensions.
* Update requirements to include numpy.