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

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