Proposal: Export retyped builtins rather than wrappers

[Thom1729]

E.g. instead of:

export function objectKeys<Type extends object>(value: Type): Array<ObjectKeys<Type>> {
    return Object.keys(value) as Array<ObjectKeys<Type>>;
}

Do:

export const objectKeys = Object.keys as <Type extends object>(value: Type) => Array<ObjectKeys<Type>>;

This saves a function call.