strictier function signatures

[untoreh]

Basically all functions with arguments any combination of Strategy AssetInstance Order Trade etc... have "loose" signatures. Meaning for example that you could call them with arguments where the strategy refers to an exchange, and an asset refers to another... They would have to be rewritten for example like:

function position!(
    s::IsolatedStrategy{Sim}, ai::MarginInstance, t::PositionTrade{P};
) where {P<:PositionSide}

to

function position!(
    s::Strategy{X,N,E,Isolated,C}, ai::AssetInstance{A,E,Isolated}, t::Trade{O,A,E,P};
) where {X,N,E<:ExchangeID,C,A<:AbstractAsset,O,P<:PositionSide}