Can not interfere enum names when starting with a number

[n-buck]

JSON enums allow enum-values to start with numbers.
Interfering the keys from the enum-values will result in an enum like i.e.

enum foo {
   0bar: "0bar",
   1baz: "1baz",
}

which is invalid in typescript.

I think the best way to handle this is to escape the keys, similar to special-characters:

enum foo {
   "0bar": "0bar",
   "1baz": "1baz",
}

I opened a PR for this Issue:
#656