Fix strange log when bad command is used

[mswiech]

I have made mistake and used command osgi:sleep 5000 (instead of shell:sleep 5000).

And this is the message I can see:

[ERROR] Failed to execute goal org.jboss.qa:karaf-maven-plugin:1.1.1:client (cxf-ssl-test-restart-amq) on project cxf-ssl-test: String index out of range: -5: java.lang.StringIndexOutOfBoundsException: String index out of range: -5 -> [Help 1]

With -X :

[ERROR] Failed to execute goal org.jboss.qa:karaf-maven-plugin:1.1.1:client (cxf-ssl-test-restart-amq) on project cxf-ssl-test: String index out of range: -5: java.lang.StringIndexOutOfBoundsException: String index out of range: -5 -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.jboss.qa:karaf-maven-plugin:1.1.1:client (cxf-ssl-test-restart-amq) on project cxf-ssl-test: String index out of range: -5
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:216)
...
Caused by: org.apache.maven.plugin.MojoExecutionException: String index out of range: -5
    at org.jboss.qa.KarafClientMojo.execute(KarafClientMojo.java:266)
    at org.jboss.qa.KarafClientMojo.execute(KarafClientMojo.java:172)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:132)

I think that this "String index out of range: -5" could be this plugins bug.