Add a few lintian tweaks for new packages

- Allow newer standards versions than we specify
- Silence warnings about some maintainer emails (gstreamer)
- Allow for packages to come from 'unstable' distribution to facilitate
backports from Debian

Change-Id: Iaf588f62e131bb8020a14c0a41d7545a1d0a4a42
diff --git a/lintian/profiles/mendel/main.profile b/lintian/profiles/mendel/main.profile
index 1d933c3..7fdb426 100644
--- a/lintian/profiles/mendel/main.profile
+++ b/lintian/profiles/mendel/main.profile
@@ -10,4 +10,5 @@
  arch-dependent-file-in-usr-share, unstripped-binary-or-object,
  statically-linked-binary, missing-depends-line,
  source-nmu-has-incorrect-version-number, changelog-should-mention-nmu,
- newer-standards-version
+ newer-standards-version, maintainer-address-causes-mail-loops-or-bounces,
+ spelling-error-in-readme-debian
diff --git a/lintian/vendors/mendel/main/data/changes-file/known-dists b/lintian/vendors/mendel/main/data/changes-file/known-dists
index 4a5ab8b..3d6fa72 100644
--- a/lintian/vendors/mendel/main/data/changes-file/known-dists
+++ b/lintian/vendors/mendel/main/data/changes-file/known-dists
@@ -3,3 +3,4 @@
 mendel-animal
 mendel-beaker
 mendel-chef
+unstable