I think I found a bug. `JsonElement.booleanOrNull`...

# serialization

[Toddobryan]

I think I found a bug. JsonElement.booleanOrNull doesn't check to see whether isString is true, so parse("true").booleanOrNull and parse("\"true\"").booleanOrNull both return true, even though I think the secord one should return null.

[sandwwraith]

It could be a bug in some case and a handful extension in other, so it really depends on how much 'strictness' do you want. You can file a GitHub issue for discussion, if you'd like