[Feature Update] Adds new Spacegrass Tile Variations to GrassGro

[Avatharian]

Adds several new spacegrass tile variations that have flowers! Whenever a Spacegrass tile is generated by GrassGro, a random variation and rotation is selected from the new tiles for variety. 

New Tiles .dmi here. Merge into Merge into /icons/turf/outdoors.dmi

[pali6]

Merged (I added the possible icon_states to grassify(), I think that's what you want?).