##### SUMMARY
Since `add_host` and `group_by` actions only modify the runtime inventory, hosts/groups/vars added by them don't survive a `meta: refresh_inventory` call (since that call completely clears the runtime inventory). 

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
InventoryManager

##### ADDITIONAL INFORMATION
After some internal discussion, the general consensus seemed to be that this behavior is an undesirable default. The `add_host` and `group_by` actions should manage a more persistent state independent of the runtime inventory, then apply their changes to the running inventory. When a `meta: refresh_inventory` occurs, the normal dynamic inventory clear/refresh should happen, then reapply the add_host/group_by state. This should probably be the default behavior, but a config switch or a different `meta` action (or an arg to it) to emulate the current behavior could also be created if necessary.

''' Generate or update inventory for the source provided '''
        parsed = False
        failures = []
        display.debug(u'Examining possible inventory source: %s' % source)
        
        b_source = to_bytes(source)
        
        if os.path.isdir(b_source):
            display.debug(u'Searching for inventory files in directory: %s' % source)
            for i in sorted(os.listdir(b_source)):
                display.debug(u'Considering %s' % i)
                
                if IGNORED.search(i):
                    continue
                
                fullpath = to_text(os.path.join(b_source, i), errors='surrogate_or_strict')
                parsed_this_one = self.parse_source(fullpath, cache=cache)
                display.debug(u'parsed %s as %s' % (fullpath, parsed_this_one))
                if not parsed:
                    parsed = parsed_this_one
        else:
            
            
            self._inventory.current_source = source