Add a simple implementation of runoff attenuation features using two velocity/time constants for the surface store such that up to a specified RAF volume operates with a specified time constant and storage beyond that utilizes the formulation in v0.2.1
Add a simple implementation of runoff attenuation features using two velocity/time constants for the surface store such that up to a specified RAF volume operates with a specified time constant and storage beyond that utilizes the formulation in v0.2.1