Introduce a smarter quadrature resolution measure

This measure is aware of element aspect-ratios in 3D and and varying 'parametrization speeds' across an element. It's also computed using the regular expression evaluator, not with custom machinery. The evaluator was made smarter as needed--such as by allowing it to operate on the 'stage 2' discretization of a layer potential source.

This quadrature resolution measure replaces panel sizes where appropriate.

@mattwala, could you take a look? I am hoping that this will address our 3D quad resolution woes.