Removed dependency on RhinoScriptProcessor and index-based queries

The ExecuteWebScript is currently hard-wired against the default RhinoScriptProcessor by the way the script is prepared for execution. With an adjustment that simply adds an import for the pre-roll script instead of resolving imports and merging, this hardwiring can be removed allowing the ExecuteWebScript and JS Console as a whole to be used with alternative script processor implementations (i.e. https://github.com/AFaust/alfresco-enhanced-script-environment).
Additionally, the JS Console currently requires the presence of an index-based search system to lookup and store scripts. This is not necessary for the purpose of locating a specific location as there are database-based alternatives, allowing the JS Console to be used when no index is available (either corrupt, being re-created or the "noindex" Search subsystem being used).