Combine institution and filing cleanup to single endpoint

[guffee23]

Create an endpoint that removes the institutions and filing data. Call into to both functions, require data needed for both in the endpoint url.

[guffee23]

The paths need to be set to the following:
/v1/cleanup/{lei} <- All institutions and filings for a LEI
/v1/cleanup/institution/{lei} <- Institutions for a LEI
/v1/cleanup/filing/{lei}/{period_code} <- Filings for a LEI for a given period
/v1/cleanup/submissions/{lei}/{period_code} <- Submissions for a LEI for a given period

Update the readme.md with the following after this update for #26