Changed in read for pull#7

@John: A lot changed after you sent the pull request so resolving conflicts was hard. I have done the changed which you have suggested here. 

Please have a look. Thanks.
Yes. I inserted "an" before "example", and "Java" after "CDAP"...if you prefer, we could say:
for an example using Java, refer to the \`CDAP SparkPageRank example