Fix bug #3 and add corresponding test case

[blumu]

This is a quick fix for #2.
This change enables the Json.Net MissingMemberHandling option which makes the Compact deserializer strict. This means that deserialization will faill if there is any member in the Json that is not present in the F# type. This is not technically required for Compact deserialization but it is needed to make the current implementation of the BackwardConmpatible serializer pass all the unit tests. In particular without this setting the following code

type NestedStructure = { subField : int}
type NestedOptionStructure = NestedStructure option 

let x= Some {subField = 456 }
let z= Default.serialize x 
z|> Compact.deserialize<NestedOptionStructure>

would deserialize to Some {subField = 0;} instead of throwing, which would then confuse the backward-compatible deserializer.

[blumu]

Note: there could be further ambiguities when deserializing type of the form Option<'a> where type 'a is a record or discriminated union with a field named Some. The latest iteration of this PR adds unit tests to cover this case and resolves the ambiguity by enforcing Json boxing of option types whenever the underlying type has an attribute named Some.