[IZPACK-1147] - Fixes for JDKPathPanel

This is to address: https://jira.codehaus.org/browse/IZPACK-1147

1. Set the installData's JAVA_HOME to the actual JAVA_HOME by default rather than the path to the running JRE
2. Apply the promptLocation Console method for JDKPathPanelConsole to allow autocompletion
3. Ensure that the JDKPathPanel.skipIfValid works for console installations if JDK is valid
4. If the default path to the JDK does not meet the requirements based on JDKPathPanel.minVersion and JDKPathPanel.maxVersion, then show user's home directory as default path rather than a blank field (like targetPanel)
5. Refactor the JDKPathPanel and synchronize its functionality through JDKPathPanelHelper. There was alot of code duplication, this will keep functionality in sync and make modifying this panel less error prone.