Support ignoring file deletions

[johnlk]

What type of PR is this? (check all applicable)

• [ ] Refactor
• [x] Feature
• [ ] Bug Fix
• [ ] Optimization
• [ ] Documentation Update

Description

This change supports ignoring files which are wholly deleted. This seems to be a common ask. The new config variable is called ignore_file_deletions and relies on the files API to determine the status of a file.

This change was inspired by #61 , but with updated patterns and tests.

How to test

I added unit tests for the new code paths to ensure everything is behaving as expected.

Link to issues addressed

• ISSUE-66

[johnlk]

cc: @OnkarRuikar