Fix bug using class in the body without capitalize

Operations with a model as a body type don't capitalize first letter of the type name. 

 The following case:

    body: {
        type: "stream"
    }

generates the following error:

    [error] package.scala:122: type stream is not a member of package com.gilt.svcstream.models
    [error]       def putByStreamId(stream: com.gilt.svcstream.models.stream,