title: Tensorflow summary scalars not showing up in tensorboard
body: <p>I have used tensorboard in several projects previously and it has worked great. When I run those projects now it still works. However, in a new project the summary scalars I have saved will not show up. The graph is there and appears correct but the "No scalar data was found" dialogue is under the scalars tab. I tried to write the simplest code I could think of as a test and it's still not working:</p>
  
  <pre><code>import tensorflow as tf
  
  tf.reset_default_graph()
  
  g = tf.Graph()
  
  with g.as_default():
  
      y = tf.Variable(1)
      initialize = tf.global_variables_initializer()
      tf.summary.scalar('thing',y)
  
  sess = tf.InteractiveSession(graph=g)
  sess.run(initialize)
  
  merged = tf.summary.merge_all()
  
  writer = tf.summary.FileWriter("path",g)
  
  for i in range(10):
      summary = sess.run(merged)
      writer.add_summary(summary,i)
  
  sess.close()
  </code></pre>
  
  <p>I'm thinking this should just give me a constant y value over 10 steps, but no scalars in tensorboard. Have I made some mistake?</p>