General service class for exporting document list from a Mongo Collec…

[luk-kaminski]

…tion.

Description

General service class for exporting document list from a Mongo Collection.
Refactoring recent permission code, so that it is in a separate class (for easier testing and reuse between different service classes that may need it)
/nocl

Motivation and Context

Preparation for investigations export.

How Has This Been Tested?

With new unit tests.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (non-breaking change)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.