add checkstyle plugins
add "nb-configuration.xml" in .gitignore file.
added Maven checkstyle plugin in rootbeer-brms-model and rootbeer-rbms-view
fix pom.xml
Merge pull request #59 from FUNProject14/ejo090/pomfix2

added Maven checkstyle plugin in rootbeer-brms-model and rootbeer-rbms-view