.travis.yml: run javadoc:javadoc to detect javadoc errors (#1148)
.travis.yml: run javadoc:javadoc to detect javadoc errors (#1148)


hazendaz/assertj-core,assertj/assertj-core,xasx/assertj-core,joel-costigliola/assertj-core,assertj/assertj-core,xasx/assertj-core,hazendaz/assertj-core,joel-costigliola/assertj-core