Update quantum_data.ipynb (tensorflow#542)

per issue 479
removed unnecessary application of newaxis (update to lines 184 & 287)
typo fix (line 613)

docs/tutorials/quantum_data.ipynb

@@ -181,7 +181,7 @@
     "(x_train, y_train), (x_test, y_test) = tf.keras.datasets.fashion_mnist.load_data()\n",
     "\n",
     "# Rescale the images from [0,255] to the [0.0,1.0] range.\n",
-    "x_train, x_test = x_train[..., np.newaxis]/255.0, x_test[..., np.newaxis]/255.0\n",
+    "x_train, x_test = x_train/255.0, x_test/255.0\n",
     "\n",
     "print(\"Number of original training examples:\", len(x_train))\n",
     "print(\"Number of original test examples:\", len(x_test))"
@@ -284,7 +284,7 @@
    "source": [
     "print(y_train[0])\n",
     "\n",
-    "plt.imshow(x_train[0, :, :, 0])\n",
+    "plt.imshow(x_train[0, :, :])\n",
     "plt.colorbar()"
    ]
   },
@@ -610,7 +610,7 @@
     "id": "yNliqKFdYacD"
    },
    "source": [
-    "Chooe some qubits and prepare the data encoding circuits:"
+    "Choose some qubits and prepare the data encoding circuits:"
    ]
   },
   {