[GeckoLib Models & Animations] "easing" in *.animation.json cannot be correctly loaded in game

[cvrunmin]

Description

While you can select different easing function, like "easeOutQuint" which has very high speed at the beginning and immediately slows down, and preview normally in BlockBench, in game, such animation is still linear.

In investigation, GeckoLib registers easing functions with full lowercase name:
https://github.com/bernie-g/geckolib/blob/bc3e5e158fc2a8b406cad04ba417a9d7778a8327/common/src/main/java/com/geckolib/animation/object/EasingType.java#L27-L59

However, the exported animation.json save the easing function in lower camel case:

"rotation": {
  "0.0": {
    "vector": [-5, 0, 0]
  },
  "0.1667": {
    "vector": [-47.5, 0, 0],
    "easing": "easeInQuart"
  },
  "0.4167": {
    "vector": [-47.5, 0, 0],
    "easing": "linear"
  },
  "0.75": {
    "vector": [-5, 0, 0],
    "easing": "easeInSine"
  }
}

and GeckoLib does not make string in lowercase before look-uping the easing function, which will default to linear function.