Merge pull request #579 from CrazyJvm/patch-1.

"in the source DStream" rather than "int the source DStream"

"flatMap is a one-to-many DStream operation that creates a new DStream by generating multiple new records from each record int the source DStream."

Author: Chen Chao <crazyjvm@gmail.com>

Closes #579 and squashes the following commits:

4abcae3 [Chen Chao] in the source DStream

docs/streaming-programming-guide.md

@@ -88,7 +88,7 @@ val words = lines.flatMap(_.split(" "))
 {% endhighlight %}
 
 `flatMap` is a one-to-many DStream operation that creates a new DStream by
-generating multiple new records from each record int the source DStream. In this case,
+generating multiple new records from each record in the source DStream. In this case,
 each line will be split into multiple words and the stream of words is represented as the
 `words` DStream.  Next, we want to count these words.