Added FluidColored to have a general implementation for dynamic color fluids

Added FluidColored to have a general implementation for dynamic color fluids.

This way mods only need to send the color value using getColor(FluidStack) and on receive set it using setColor(FluidStack, int).

An example of a fluid using this would be paint. If a mod would have a block to turn dyes into paint fluid and a block that can mix these dyes or fluids to get all possible RGB values.