Merge branch 'bug32240_32242_042' into bug32240_32242_master

Merge:
* libzstd-dev from ticket32242_042
* coccinelle from master

.travis.yml

@@ -119,8 +119,7 @@ addons:
       - libnss3-dev
       - libscrypt-dev
       - libseccomp-dev
-      ## zstd doesn't exist in Ubuntu Trusty
-      #- libzstd
+      - libzstd-dev
       ## Optional build dependencies
       - coccinelle
       - shellcheck

changes/ticket32242

+  o Testing (continuous integration):
+    - Use zstd in our Travis Linux builds. Closes ticket 32242.