travis: attempt to add Coverity integration

Not sure if this will work. Probably not, because it seems Coverity will
be missing some required dependencies.

.travis.yml

@@ -15,6 +15,7 @@ branches:
   only:
     - master
     - ci
+    - coverity_scan
 
 matrix:
   exclude:
@@ -38,3 +39,17 @@ notifications:
       - "irc.freenode.org#mpv-player-dev"
     on_success: change
     on_failure: always
+
+env:
+  global:
+   - secure: "H21mSRlMhk4BKS0xHZvCFGJxteCP0hRVUxTuNfM2Z9HBsyutuLEYMtViLO86VtM+Tqla3xXPzUdS4ozLwI72Ax/5ZUDXACROj73yW6QhFB5D6rLut12+FjqC7M33Qv2hl0xwgNBmR5dsm1ToP37+Wn+ecJQNvN8fkTXF+HVzOEw="
+
+addons:
+  coverity_scan:
+    project:
+      name: "mpv-player/mpv"
+      description: "Build submitted via Travis CI"
+    notification_email: mpv-team@googlegroups.com
+    build_command_prepend: "./bootstrap.py && ./waf configure"
+    build_command:   "./waf build"
+    branch_pattern: coverity_scan