Addes a heat-map representing the data in world (an EnvironmentFile object)
    to the current plot.

    kwargs:
               palette - a seaborn palette (list of RGB values) indicating
                         how to color values. Will be converted to a continuous
                         colormap if necessary
               denom   - the maximum value of numbers in the grid (only used
                         if the grid actually contains numbers). This is used
                         to normalize values and use the full dynamic range of
                         the color pallete.

def plot_world(world, **kwargs):
    """
    Addes a heat-map representing the data in world (an EnvironmentFile object)
    to the current plot.

    kwargs:
               palette - a seaborn palette (list of RGB values) indicating
                         how to color values. Will be converted to a continuous
                         colormap if necessary
               denom   - the maximum value of numbers in the grid (only used
                         if the grid actually contains numbers). This is used
                         to normalize values and use the full dynamic range of
                         the color pallete.
    """
    denom, palette = get_kwargs(world, kwargs, False)
    world = color_grid(world, palette, denom, True)
    plt.tick_params(labelbottom="off", labeltop="off", labelleft="off",
                    labelright="off", bottom="off", top="off",
                    left="off", right="off")
    # plt.tight_layout()
    plt.imshow(world, interpolation="none", zorder=1)
    axes = plt.gca()
    axes.autoscale(False)