Adds field versions of the operations from Attribute Statistic, can
support grouping via Group IDs. These operations are added as separate
nodes: `Field Average`, `Field Min & Max`, & `Field Variance` which
group the different statistic operations according to their use.
Supported Data Types:
- Field Average - (Float, Vector)
- Field Min & Max - (Float, Integer, Vector)
- Field Variance - (Float, Vector)
Pull Request: https://projects.blender.org/blender/blender/pulls/134640