Improve project quality checks

[AlejandroRivera]

• Configure CheckStyle
• Configure FindBugs
• Configure PMD
• Configure SonarQube
• Consider using Walkmod
• Research and configure code quality reporting systems (similar to Coveralls but for quality)
• Checkers Framework
• Check dependency versions (versioneye.com)
• Check Licensing issues (versioneye.com)