Doc update for 2.4rc1
Added updated changelog.
Added 2.4rc1 to the changelog
Cleaned up javadocs.
Doc updates.
Reformat to make the page rebuild.
Doc updates for 2.4.2
Disable jekyll processing.
Changelog update.
Changelog update.

Change-Id: Idf0e3df642b04429c481f7f21e98e7373d20f339
Updated changelog