Implemented querying machines

Added new helper functions: positive_filters and negative_filters
Changed the query action map into a constant: FILTER_ACTION_MAP
Added check_filter_batch_match function to catch the difference between groups of positive and negative filters
Corrected multiple key errors in getters
Added filter_machines, which allows for querying machines from the CLI
Added a clearer message when a certain object type query is not implemented

LCVcode / jockey