Bug#318630: Design TRUSTED support

[Goswin von Brederlow <goswin-v-b@web.de>]

Any objections to the proposed design for this feature?

- deb [key=0x1AB52325534,0x3475BDF478] ...
  Only accept signatures by one of the listed fingerprints

- deb [keyring=foobar.gpg] ...
  Use foobar.gpg to verify the signatures and only foobar.gpg.

deb [trust=always|never] ....
  Ignore the Release signature and just always or never trust the
  source. "always" would be for file:// or sources on the local
  network where you don't care if it is unsigned. "never" would be for
  repositories you want to always be asked before they are used and
  which should not replace packages from more trusted repositories.

MfG
	Goswin