Revision 1868597

Improved: Use ‘checkstyle’ linting tool
(OFBIZ-11251)

Linting [1] is a software engineering practice which make the code more
readable and maintainable by improving its consistency and avoiding
potential programming mistakes.  Gradle provides a core plugin for the
‘checkstyle’ tool [2][3] which implement a linting facility for the Java
language.

The check is done with the ‘gradlew check’ command.

There are currently a lot reported errors that will need to be fixed
incrementally in the future.  We ensure that new errors will not be
introduced by defining a global threshold of “allowed” errors
corresponding to the sum of errors found in the framework and in the
official plugins.

[1] https://en.wikipedia.org/wiki/Lint_(software)
[2] https://checkstyle.org/
[3] https://docs.gradle.org/current/userguide/checkstyle_plugin.html

Thanks: Taher Alkhateeb and Jacques Le Roux for their feedback