Replace verbose by log level

I'd like to be able to specify the log level if I do a sonar analysis.
E. G. when starting an analysis from a cron job on linux, I want the log level to be WARN, to get the warnings mailed.
Currently this can only be done by filtering out INFO lines from the output with various patterns.
I'd like to be able to control this from sonar-runner with a command line switch.
So here is the sonarqube-runner part, the according pull request for the sonarqube part is at https://github.com/SonarSource/sonarqube/pull/38