Bump version to 6.1.0

Merge pull request #568 from treeform/vmath_v3c

Use the new vmath v3 with CCW angles.

Merge pull request #552 from Nimaoth/master

added support for open type format 12

Merge pull request #526 from treeform/guzba

up nimsimd dep to fix arm64 simd

Merge pull request #523 from treeform/guzba

use crunchy for crc32

Merge pull request #518 from treeform/guzba

5.0.4

Merge pull request #516 from treeform/guzba

5.0.3

Merge pull request #514 from treeform/guzba

produce smaller pngs

Merge pull request #497 from treeform/guzba

fix smooth draw fuzz