Bug#704136: lintian: treat git-dch --snapshot packages as local packages to avoid NMU warnings

[Helmut Grohne <h.grohne@cygnusnetworks.de>]

Package: lintian
Version: 2.5.10.4
Severity: wishlist

The jenkins-debian-glue uses git-dch --snapshot to increase the version number
before building. Unfortunately it also changes the email address in the topmost
changelog entry, so lintian believes such a package to be a NMU. Now lintian
already has some logic to avoid this for "local packages". I'd like lintian to
tread git-dch --snapshot packages the same. A typical changelog looks like his:

$package ($origversion~$unixseconds~1.gbp$abbrevcommitid) …

  ** SNAPSHOT build @$longcommitid **

  $origchangelog

  -- $changedmaintainer

I suggest to also set the $changelog_mentions_local variable in checks/nmu if
the first line contains the words /\bsnapshot\s+build\b/i.

Helmut