OPEN - task #464: Olog client spams CONFIG logs when created 
http://github.com/ControlSystemStudio/cs-studio/issues/issue/464

Adding a preference to define the logging level for the jersey clients
OPEN - task #464: Olog client spams CONFIG logs when created 
http://github.com/ControlSystemStudio/cs-studio/issues/issue/464

Should not be commented
Merge pull request #521 from shroffk/3.3.x

3.3.x