First cut at Javascript docs

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Added #ifndef PROPSI_NO_ERROR_CATCH to PropsSI to disable error catching to close https://github.com/CoolProp/CoolProp/issues/84

This is done so that debuggers can halt at the error for easier introspection.

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
Fixed coolprop function is EES by calling the correct function

Signed-off-by: Ian Bell <ian.h.bell@gmail.com>