Continuos builds/deployment and PR workflow validation improvement #269

In 2014 java_client was the very small library. Since that time it has grown to framework (I think) and it is still growing. Number of contributors increases.

• 1. We need to automate the building and deployment.
• 2. We need to enhance PR state workflow.

The first we could do with Jenkins CI or Travis CI (like the Selenium project does).

The second should include:

• the PR checking with CI (it is connected to point 1)
• (optionally) the code style checking