How to best send command line args to local dynamodb docker container

Sorry if this is the wrong git repo - I couldn't find where the dockerfile for `amazon/dynamodb-local` was being maintained.

2 questions here:

1. Currently, to send command line args as described here https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DynamoDBLocal.UsageNotes.html it looks like I need to send the full args to the java process instead of just the args to configure the dynamodb server. So instead of running `docker run -it --rm amazon/dynamodb-local -sharedDb` I need to run `docker run -it --rm amazon/dynamodb-local -Djava.library.path=./DynamoDBLocal_lib -jar DynamoDBLocal.jar -sharedDb`
Would it be possible to change the entrypoint/cmd of the dockerfile to handle the java args for you and the user just pass in the extra arguments? I think the more common use case is to just specify the dynamodb args, but if a user wanted to modify the java args they should be able to override the entrypoint in their own `docker run`

2. What directory in the container should I mount if I want to persist the .db file?