Description of problem:
If the rhq-server.properties file is missing the property rhq.server.log-level, the JBoss ON server fails to start:

 JBAS014802: Cannot resolve expression 'expression "${rhq.server.log-level}"' -- java.lang.IllegalStateException: Failed to resolve expression: ${rhq.server.log-level}
	at org.rhq.common.jbossas.client.controller.LoggingJBossASClient.setLoggerLevel(LoggingJBossASClient.java:92) [rhq-jboss-as-dmr-client-4.9.0.JON320GA.jar:4.9.0.JON320GA]


This is common when upgrading from a previous version of JBoss ON that did not use this property. 

As with any property definition, a reasonable default should be used. In this case, the default seems to be INFO so it would make sense that the property expression use INFO as its default value and that this not be dependent on the rhq-server.properties file itself.

Version-Release number of selected component (if applicable):
3.2.0

How reproducible:
Always

Steps to Reproduce:
1. Extract JBoss ON 3.2 server archive.
2. Set server bind address in rhq-server.properties.
3. Remove rhq.server.log-level property from rhq-server.properties file.
4. Run install:
      rhqctl install

Actual results:
Install will fail with error:

    14:52:59,380 ERROR [org.rhq.enterprise.server.installer.Installer] The installer will now exit due to previous errors: org.rhq.common.jbossas.client.controller.FailureException: Failed request: JBAS014802: Cannot resolve expression 'expression "${rhq.server.log-level}"' -- java.lang.IllegalStateException: Failed to resolve expression: ${rhq.server.log-level}
        at org.rhq.common.jbossas.client.controller.LoggingJBossASClient.setLoggerLevel(LoggingJBossASClient.java:92) [rhq-jboss-as-dmr-client-4.9.0.JON320GA.jar:4.9.0.JON320GA]
        at org.rhq.enterprise.server.installer.ServerInstallUtil.configureLogging(ServerInstallUtil.java:187) [rhq-installer-util-4.9.0.JON320GA.jar:4.9.0.JON320GA]
        at org.rhq.enterprise.server.installer.InstallerServiceImpl.install(InstallerServiceImpl.java:333) [rhq-installer-util-4.9.0.JON320GA.jar:4.9.0.JON320GA]
        at org.rhq.enterprise.server.installer.Installer.doInstall(Installer.java:116) [rhq-installer-util-4.9.0.JON320GA.jar:4.9.0.JON320GA]
        at org.rhq.enterprise.server.installer.Installer.main(Installer.java:57) [rhq-installer-util-4.9.0.JON320GA.jar:4.9.0.JON320GA]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_05]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_05]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_05]
        at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_05]
        at org.jboss.modules.Module.run(Module.java:270) [jboss-modules.jar:1.2.2.Final-redhat-1]
        at org.jboss.modules.Main.main(Main.java:411) [jboss-modules.jar:1.2.2.Final-redhat-1]


Expected results:
Install should succeed with no error.