i16 missing instantiations locator script

[bkiahstroud]

Ref

• The wrong child works are attached to parents scientist-softserv/ams#16

Add service that will help in locating all the missing child instantiations. Currently, it's sole purpose is mapping all possible Asset IDs to each unique instantiation identifier. For example:

{ "inst_id_a" => ["asset id 1", "asset id 2"] }

The results are written to JSON files. Each provided "search directory" gets its own JSON file so that multiple directories can be searched at once without trying to write to the same file. In the future, all the resulting JSON files should be merged into a single file since the same instantiation identifier could appear multiple times across different search directories.