Added a few more math funcs

[kuzminrobin]

Added

    function Sin (d : Double) : Double      sin__body
    function Cos (theta : Double) : Double  cos__body
    function Tan (d : Double) : Double      tan__body

    function ArcCos (x : Double) : Double   arccos__body
    function ArcSin (y : Double) : Double   arcsin__body
    function ArcTan (d : Double) : Double   arctan__body

    function Sinh (d : Double) : Double     sinh__body
    function Cosh (d : Double) : Double     cosh__body
    function Tanh (d : Double) : Double     tanh__body

    function IEEERemainder (x : Double, y : Double) : Double    
                                            ieeeremainder_body

Resolves #501

[swernli]

Looks good to me!

[IrinaYatsenko]

LGTM!