fix mongo_db_plugin filter deficiency to allow any combination of receiver,action,actor

[venediktov]

@heifner , @arhag in the current implementation of mongo_db_filters only subset of permutations of {receiver, action,actor} is allowed which makes it difficult to fine tune what gets written to backend store .

In our case we were looking to do --mongodb-filter-on ":issue:" --mongodb-filter-on ":issue4snap:" --mongodb-filter-on ":transfer:

The format of the filter is receiver:action:actor and current implementation only allows receiver:action: but does not allow omitting receiver like :action:actor or :action: ( for all actors)

[heifner]

There is already changes in a PR for filtering. I'll include these into that PR #5670

[venediktov]

Thank you @heifner ! It looks like if we merge with PR #5670 we need to change --mongodb-filter-on option description as to something like

Any combination of "receiver:0:actor" , "0:action:actor" , "0:0:actor" , "0:action:actor" , "0:action:0" including "0:0:0" which can also be denoted as simply passing "*" to this option

[wanderingbort]

Closing in favor of consolidating work into #5670