Allow preprocessing to access macros like {host.host} so json results can be processed for just information related to host

Allow preprocessing to access macros like {host.host} and {$macros} in json paths, XML  and java script filtering methods. 

This will allow processing of json/MXL results that come back from external systems to be filtered to information related to host we are interested in because otherwise the unable to filter.

JavaScript access to any macro would also allow much more complex processing options to be enable.