Parameterized type violated when deserializing an Option

I can deserialize just about anything into an `Option`:

``` scala
case class Foo(integer: Option[Int])

object OptionFail {
val mapper = new ObjectMapper() with ScalaObjectMapper
mapper.registerModule(DefaultScalaModule)

def main(args: Array[String]) {
val json = """{"integer" : "a cat"}"""
println(mapper.readValue[Foo](json))
// prints: Foo(Some(a cat))
}
}
```

Using:

```
libraryDependencies ++= Seq(
"com.fasterxml.jackson.core" % "jackson-databind" % "2.7.3",
"com.fasterxml.jackson.module" % "jackson-module-scala_2.11" % "2.7.2"
)
```