Changes

** showblock to compliment hideblock

** showblock to compliment hideblock

** fullscreen block

** fullscreen block

** Cartesian and polor coordinate blocks

** Cartesian and polar coordinate blocks

** color blocks

** color blocks

** editible macros (used for presentation blocks)

** editable macros (used for presentation blocks)

** labels on coordinate-grid overlays

** labels on coordinate-grid overlays

** more complete support in non-Sugar environments

** more complete support in non-Sugar environments