[PATCH] travis: use ppa:notmuch/notmuch

[Daniel Kahn Gillmor]

https://launchpad.net/~notmuch/+archive/ubuntu/notmuch/+packages
contains backports of gmime and gpgme and related cryptographic tools
to ubuntu xenial.

I tried to do a simple backport of gmime alone, and it failed due to
the older gpgme in xenial, so this setup resolves those problems.

This should allow us to continue to use the Travis continuous
integration build on the release branch.

Signed-off-by: Daniel Kahn Gillmor <dkg at fifthhorseman.net>
---
 .travis.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.travis.yml b/.travis.yml
index 90a1cc56..f9516bde 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ addons:
   apt:
     sources:
     - sourceline: 'ppa:xapian-backports/ppa'
+    - sourceline: 'ppa:notmuch/notmuch'
     packages:
     - dtach
     - libxapian-dev
-- 
2.20.1