Major new ForceField improvements/features: Implements GBSA support and constraints for the SMIRNOFF (formerly SMIRFF) ForceField functionality; updates SMIRNOFF spec substantially to include these changes. Makes various fixes to smirff99Frosst prototype general small molecule force field.
On smarty/smirky chemical space samplers: improves small molecule tests sets (such as MiniDrugBank) used for smarty and smirky samplers. Fixes issues with smirky sampler. Improved smarty/smirky examples and README clarifications.