title: Can't remove collection in mongoDB
body: <p>I just started learning mongoDB and I noticed a collection which is removed by .remove() command still exist after the executing.
  am I doing something wrong or this is how it's supposed to work?</p>
  
  <p>by using mongo</p>
  
  <pre><code>use testDB
  db.stats() // returns "db" : "testDB","collections" : 0,"objects" : 0 
  //and db.getCollectionNames() returns nothing as well
  db.testCollection.insert({ test : 'abc'})
  db.getCollectionNames() // [ "system.indexes", "testCollection" ]
  db.testCollection.remove()
  db.testCollection.find() // returns nothing
  db.getCollectionNames() // [ "system.indexes", "testCollection" ]
  db.stats() // "db" : "testDB","collections" : 3,"objects" : 4
  </code></pre>