Prepare Spark api docs for offline browsing

Get the source code file from Spark website

https://spark.apache.org/downloads.html

Use command as

mvn scala:doc

This will build scaladocs for all the projects.

Go to required project target folder and seen what is needed.

If you want nightly release code for latest version

Go to URL below to get the code and see docs

http://people.apache.org/~pwendell/spark-nightly/

https://repository.apache.org/content/repositories/snapshots/org/apache/spark/