Feature/enum key prefix name

[alkalinecoffee]

Adds a new enumKeyPrefix value to include in our schema, allowing the developer to specify a custom prefix for enum keys.

For instance, an enum value 1080p60 would typically produce a key like 1080P_60, but this would be disallowed as it starts with a number.

By specifying the enumKeyPrefix, we can still use a mix of string and numerical values but can reference them with a valid stringified key.

"VideoMode": {
  "enumKeyPrefix": "mode",
  "enum": [
    "1080p50",
    "1080p60",
    "unknown"
  ]

The above would produce enums such as:

MODE_1080P_50 = "1080p50"
MODE_1080P_60 = "1080p60"
MODE_UNKNOWN = "unknown