RF: move code chunks into SecFileArchive
RF: openssl as property, move away from global var
RF auto-trigger at init; better modularity, SecFileArchive

- e.g., pub='u' at init = trigger implicit .encrypt('u')
- destroy_status
- move away from global codec (bad), keep in SecFile instance (good);
  same for OPENSSL path
- better SecFileArchive
- rotate is broken now