World: added first version.
World: fixed initial heightmap height to 0.5, changed initial max_elevation to +/- 0.5, fixed midpoint displacement
world_demo: updated demo to the World
World: moved the first step of generation to generate_step1()
World: added generate_step2() - heightmap correction
World: changed grid[] to have all three dimensions stored
World: added generate_step3() - flood fill for the sea
World: fine-tuned generate_step2() a bit
lib/misc.js: added distance_2d()
world_demo: updated
World: added a quicker flood fill generate3_quick(), thx @williammalone
World: removed land type "coast", moved coast rendering into world_demo.js
World: added a fake lighting calculation in generate_step4(), world_demo: added the display of the lighting
World: updated some comments
World: modified generate_step2() to have a random number of points
World: added normalization in the first generation step
world_demo: modified the displays of height maps
World: fine-tuned generate_step2()
World: grid_width and grid_height are now stored in map_size, renamed grid to map, updated world_demo accordingly
World: moved flood filling to a separate floodFill method, updated step3 generation accordingly