title: Object id after update command mongoskin
body: <p>While inserting in mongodb by mongoskin i could get object id by following. Which is working absoultely well</p>
  
  <pre><code>     db.collection('test').insert({
       version: nc.version,
       }, function (err, result) {
   // This would give me objectID of nre
      console.log('creating new version ', result.ops[0]._id);
           }
     })
  </code></pre>
  
  <hr>
  
  <p>While update with {upsert:true} in collection i couldn't find anything </p>
  
  <pre><code>           db.collection('test').update({labId: lab_id},{$set:
              {
              version: nc.version,
          }},{upsert:true}, function (error, result) {
  
               if (error){
                   // If there is error then
                   console.log("Error occured while adding in system");
               }
              console.log('Result is  ', result);
           })
  </code></pre>
  
  <p>Result what is print is like this one. So i would like to know where i could find my objectid (i.e. _id which we get after object is added in mongodb) </p>
  
  <pre><code> Result is  {
    result: { n: 1, nModified: 0, upserted: [ [Object] ], ok: 1 },
    connection: 
     Connection {
       domain: null,
       _events: 
        { error: [Object],
          close: [Object],
          timeout: [Object],
          parseError: [Object] },
       _eventsCount: 4,
       _maxListeners: undefined,
       options: 
        { host: 'localhost',
          port: 27017,
          size: 5,
          connectionTimeout: 30000,
          socketTimeout: 30000,
          keepAlive: true,
          keepAliveInitialDelay: 0,
          noDelay: true,
          ssl: false,
          checkServerIdentity: true,
          ca: null,
          cert: null,
          key: null,
          passPhrase: null,
          rejectUnauthorized: false,
          promoteLongs: true,
          promoteValues: true,
          promoteBuffers: false,
          reconnect: true,
          reconnectInterval: 1000,
          reconnectTries: 30,
          domainsEnabled: false,
          disconnectHandler: [Object],
          cursorFactory: [Object],
          emitError: true,
          socketOptions: {},
          clientInfo: [Object],
          readPreference: [Object],
          native_parser: true,
          promiseLibrary: [Function: Promise],
          bson: BSON {} },
       id: 0,
       logger: Logger { className: 'Connection' },
       bson: BSON {},
       tag: undefined,
       messageHandler: [Function],
       maxBsonMessageSize: 67108864,
       port: 27017,
       host: 'localhost',
       keepAlive: true,
       keepAliveInitialDelay: 0,
       noDelay: true,
       connectionTimeout: 30000,
       socketTimeout: 30000,
       destroyed: false,
       domainSocket: false,
       singleBufferSerializtion: true,
       serializationFunction: 'toBinUnified',
       ca: null,
       cert: null,
       key: null,
       passphrase: null,
       ssl: false,
       rejectUnauthorized: false,
       checkServerIdentity: true,
       responseOptions: 
        { promoteLongs: true,
          promoteValues: true,
          promoteBuffers: false },
       flushing: false,
       queue: [],
       connection: 
        Socket {
          connecting: false,
          _hadError: false,
          _handle: [Object],
          _parent: null,
          _host: 'localhost',
          _readableState: [Object],
          readable: true,
          domain: null,
          _events: [Object],
          _eventsCount: 8,
          _maxListeners: undefined,
          _writableState: [Object],
          writable: true,
          allowHalfOpen: false,
          destroyed: false,
          _bytesDispatched: 2134,
          _sockname: null,
          _pendingData: null,
          _pendingEncoding: '',
          server: null,
          _server: null,
          _idleTimeout: 30000,
          _idleNext: [Object],
          _idlePrev: [Object],
          _idleStart: 3254,
          read: [Function],
          _consuming: true },
       writeStream: null,
       hashedName: '29bafad3b32b11dc7ce934204952515ea5984b3c',
       workItems: [ [Object] ],
       buffer: null,
       sizeOfMessage: 0,
       bytesRead: 0,
       stubBuffer: null },
    message: 
     Response {
       parsed: true,
       index: 126,
       raw: &lt;Buffer 7e 00 00 00 c0 90 00 00 03 00 00 00 01 00 00 00 08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 5a 00 00 00 10 6e 00 01 00 00 00 10 6e 4d ... &gt;,
       data: &lt;Buffer 7e 00 00 00 c0 90 00 00 03 00 00 00 01 00 00 00 08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 5a 00 00 00 10 6e 00 01 00 00 00 10 6e 4d ... &gt;,
       bson: BSON {},
       opts: 
        { promoteLongs: true,
          promoteValues: true,
          promoteBuffers: false },
       length: 126,
       requestId: 37056,
       responseTo: 3,
       responseFlags: 8,
       cursorId: Long { _bsontype: 'Long', low_: 0, high_: 0 },
       startingFrom: 0,
       numberReturned: 1,
       documents: [ [Object] ],
       cursorNotFound: false,
       queryFailure: false,
       shardConfigStale: false,
       awaitCapable: true,
       promoteLongs: true,
       promoteValues: true,
       promoteBuffers: false,
       hashedName: '29bafad3b32b11dc7ce934204952515ea5984b3c' } }
  </code></pre>