A layer to be used as a base to fill the world with a single biome. Good for when 
you want a single base biome, such as in the Jungle_Islands preset example.



Constructor:
    Arguments:
        long
    Argument Usage:
        layer base seed
    Notes:
        Constructs the layer with the single biome set to 0/"Ocean".

Constructor:
    Arguments:
        long, Non_Null_Biome_ID
    Argument Usage:
        layer base seed, biome ID
    Notes:
        Constructs the layer and sets the biome it will fill the world with.

setBiome:
    Arguments:
        Non_Null_Biome_ID
    Usage:
        biome ID
    Notes:
        Sets the biome this layer will fill the world with.

