Extend karaf command to support the following syntax:
$ ./mop karaf:0.9.0-SNAPSHOT --commands 'features:addUrl mvn:org.fusesource.cloudmix/features/1.3-SNAPSHOT/xml/features ; features:install cloudmix.agent'
so as to run a secondary karaf client with: "features:addUrl mvn:org.fusesource.cloudmix/features/1.3-SNAPSHOT/xml/features ; features:install cloudmix.agent"