title: Why is lein ring uberwar not including main manifest attribute
body: <p>when I invoke java -jar my-application.war 
  after using lein ring uberware 
  I receive a response of no main manifest attribute, in my-app.war
  here is my code:</p>
  
  <p>the namespace below provides the :gen-class and -main function which are needed:</p>
  
  <pre><code> (ns nutrif.core
    (:require [ring.middleware.params]
              [ring.middleware.resource :refer [wrap-resource]]
              [ring.adapter.jetty]
              [clojure.java.io :as io])
    (:gen-class))
  
  
  
  (defn handler [request]
    {:status 200
     :header {"Content-Type" "text/html"}
     :body (io/input-stream (io/resource "public/index.html"))})
  
  (def app
    (wrap-resource handler "public"))
  
  
  (defn -main
    [&amp; [port]]
    (let [port (Integer. (or port
                             (System/getenv "PORT")
                             8080))]
      (ring.adapter.jetty/run-jetty #'app {:port  port
                                           :join? false})))
  </code></pre>
  
  <p>Here is the my project.clj which points to the namespace with the -main function. What am I missing ?</p>
  
  <pre><code>(defproject nutrif "0.1.0-SNAPSHOT"
    :description "FIXME: write description"
    :url "http://example.com/FIXME"
    :license {:name "Eclipse Public License"
              :url "http://www.eclipse.org/legal/epl-v10.html"}
    :dependencies [[org.clojure/clojure "1.6.0"]
                   [ring "1.3.0"]
                   [ring/ring-jetty-adapter "1.3.0"]]
    :plugins [[lein-ring "0.8.11"]]
    :dev-dependencies [[ring-serve "0.1.2"]
                       [javax.servlet/servlet-api "2.5"]]
    :ring {:handler nutrif.core/app
           :resource-paths [resources public]}
  
    :main nutrif.core
    :aot [nutrif.core])
  </code></pre>