RECOVERY: Add fromOrigin to character positioning (#2991)

[AbnormalPoof]

About this pull request

This pull request was made to recover #2991 which was closed due to inactivity, as the author no longer appears to be active on the repository.
If this pull request is merged, the original author will receive credit instead of me.

NOTE: If the original author returns to update the original pull request, this pull request will be closed.

Original pull request description

Adds a fromOrigin property to stage character data (defaults to true)

"bf": {
	"zIndex": 300,
	"position": [4200, 2850],
	"fromOrigin": false,
	"cameraOffsets": [-300, -300]
},

It set to true, everything just acts like normal, but if you turn it off, it positions the character in absolute coordinates (also using character position offsets), ignoring the feet position and horizontal center. Pretty useful when moving stuff from old engines.