Fix to avoid reading a file when no source is given

- file.managed was loading into memory the destination file even if no
  `source`, `contents` nor `contents_pillar` was specified. Changed it
  to force `replace` to False if no source was given
Merge branch 'develop' of https://github.com/saltstack/salt into develop
Erased some trailing whitespace
Merge pull request #13022 from mirath/develop

Forced replace to be False in file.managed when no source is specified.