Problem:
- Files such as /etc/passwd are not included
- I don't think anyone is comfortable adding them because the data they contain is particularly sensible.

Approach:
- For /etc/passwd for example, replacing the account field by its SHA-1, every character in the GECOS field by 'x' would still allow a support engineer to determine if a username is defined there, if yes its shell, etc.
- Such filters belong in the module itself and not in the core of sosreport

Proposed solution:

- When including the file, the module should be able to specify a filter method.
- We should allow per-line filters (fast and simple), filters that receive the file contents as a string and return the stored contents as another