Comment 0 for bug 497694

The following points were raised during https://code.launchpad.net/~vila/bzr/deprecation-warning-preference/+merge/16233

- the actual implementation use a single global variable for the whole code base,
  forget about being warned for the second repo accessed (or the 20th for bzrlib users),
  that should be implemented as a repo attribute instead,
- working trees can raise format deprecation warnings too, they should use the new
  facility (I don't think we want to proliferate warning variables gratuitously)
- hpss remote repositories doesn't raise the warning locally (AFAICS but feel free
  to prove me wrong),
- no distinction is made between read and write access (I'm not sure I understand
  the need here),
- there is no config file for repositories were such an option can be specified.