[typo] consistently use commas in operator list

Follow on from 1cdaeaaa4fbf02a7388f1fcbea1c86ef0ea32fed.
fix for WARNING during build
Update UnusedImportsCheck to correctly detect classes in parameters and inline tags nested within block tags.
fixing checkstyle issues
Fixing even more checkstyle issues
sonar banner was added
travis plugin and profile for coverall.io
travis plugin and profile for coverall.io
coverage banner was added
fix for typo
usage of coberture istead of jacoco
usage of cobertura in yml
jacoco now should works fine
jacoco now should works fine
fix for build problem, exclusion is provided
cleanup
Java doc was extended for Docklets to explain their role in project
fix for build failure
partial making of test inputs compilable
twitter banner was adde, image created from https://about.twitter.com/resources/buttons#follow
attempt to make test testLoadFromURL stable
fix for previous commit, formatting was fixed to pass on CI