MAINT: add reqs to docs
MAINT: add reqs to docs

mnicholl/MOSFiT,mnicholl/MOSFiT,guillochon/FriendlyFit,villrv/MOSFiT,guillochon/MOSFiT,guillochon/MOSFiT,mnicholl/MOSFiT,bmockler/MOSFiT,bmockler/MOSFiT,guillochon/MOSFiT,villrv/MOSFiT