Better Travis Script

[hendrikebbers]

Based on fixing #549 and #527 I found a nice tutorial how the sonaqube, github pages etc. build steps can be externalized and better handled in travis. See this links:

https://benlimmer.com/2013/12/26/automatically-publish-javadoc-to-gh-pages-with-travis-ci/ https://github.com/ReadyTalk/swt-bling/blob/master/.utility/push-javadoc-to-gh-pages.sh