The plugin is configured to diff the current version against last released version of the API.
Unlike the jdiff task run by ant, this plugin generates diff on a per module basis. So the script used to generate latest docs is updated to copy over per module API diffs into a single directory with a index page that links to each module's diffs.
Also fixed travis CI config to remove the docs configuration since the javadoc
and api diffs are now generated using maven.
PiperOrigin-RevId: 345697612
