XD-2044 Add SFTP source module

- Add module options and config
- Add tests
The only caveat though is that, if we options like "--password=123 --privateKey=test" (without passPhrase for example) then this returns true. In cases where someone have distinct properties in modules.yml and override something via cmd line without providing passPhrase, then it still go through. Same is the case with having all the values set.