Enhance brush tool and fix some bugs

[Firigion]

Brush has as of now enough functionality to work with a few brush types and a decent framework to add more brushes. There's still things that need working on, tho:

BUGS:

• When starting a selection with the wand and switching to the brush, the selection is doesn't go away.
• When registering a block or placable item as brush, activating it at reach distance will palce said block or item.
• Most shape brushes don't behave properly with undo

ENHANCEMENTS:

• Make a better list when calling brush list
• Make a better (more informative/prettyer format/interactive) info when calling brush info
• Add -h support for existing shapes

FURTHER ADDITIONS

• Add paste brush (paste current clipboard if brush paste [latest], paste the clipboard that was saved when the brush was created or the one at index i if brush paste fixed [i])
• Add non square prisms: polygon and star-shaped
• Add pyramid. Both this and the previous brush need a good algorithm to fill the interior of a convex shape
• Add cone brush
• Add cylinder brush
• Add ellipsoid brush
• Add cuboid brush
• Add spray paint: brush spray ball <block> <radius> [density] makes a shpere filled with random block, probably following some normal density curve, centeread at the origin of the ball. brush spray flat<block> <radius> [density] only places block on the surfase the palyer is looking at. Maybe do some random ray tracings from the palyer or something like that?
• Add biome brush
• Add butcher brush?
• Add trace line brush (generates a line between clicked block and player)
• Add smoothen and nosify brush (along with commands for those)
• Add plop feature brush
• Add hollow brush (hollow out the connex blob of blocks clicked)
• Add outline brush

World edit also has Gravity brush, Forest brush and Extinguish brush, but idk abut those.

I'll edit this comment with further suggestions.

[Ghoulboy78]

Gravity brush is basically pasting a structure as falling blocks, so they fall down and stack, or break.

[Firigion]

There are still some important things on this list, shouldn't have linked the PR.