Merge pull request #5 from feber/patch-1

Fix errata: 'pwer' => 'power'

3. Working with text files.ipynb

@@ -908,7 +908,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Let us investigate yet another way to create our data frame, this time in one-shot (this line is more difficult to understand, but it shows you the pwer that DataFrames.jl gives you when working with data, in part 4 of the tutorial we will give some more examples of supported transformations):"
+    "Let us investigate yet another way to create our data frame, this time in one-shot (this line is more difficult to understand, but it shows you the power that DataFrames.jl gives you when working with data, in part 4 of the tutorial we will give some more examples of supported transformations):"
    ]
   },
   {