title: Cannot find module 'handler' when running simple lambda deployed by serverless
body: <p>I am trying to start learning serverless / lambda so I created a simple lambda and deployed it with serverless which worked.</p>
  
  <p>However when I want to test the endpoint of the lampbda I get a <code>502</code> back. When I look in the logs it tells me that it can not find the module <code>handler</code> which does not make any sense...</p>
  
  <p>here is the log:</p>
  
  <pre><code>{
  "errorType": "Runtime.ImportModuleError",
  "errorMessage": "Error: Cannot find module 'handler'\nRequire stack:\n- 
  /var/runtime/UserFunction.js\n- /var/runtime/index.js",
   "trace": [
      "Runtime.ImportModuleError: Error: Cannot find module 'handler'",
  "Require stack:",
  "- /var/runtime/UserFunction.js",
  "- /var/runtime/index.js",
  "    at _loadUserApp (/var/runtime/UserFunction.js:100:13)",
  "    at Object.module.exports.load (/var/runtime/UserFunction.js:140:17)",
  "    at Object.&lt;anonymous&gt; (/var/runtime/index.js:43:30)",
  "    at Module._compile (internal/modules/cjs/loader.js:1158:30)",
  "    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1178:10)",
  "    at Module.load (internal/modules/cjs/loader.js:1002:32)",
  "    at Function.Module._load (internal/modules/cjs/loader.js:901:14)",
  "    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)",
  "    at internal/main/run_main_module.js:18:47"
  ]
  }
  </code></pre>