Allow fuzzer failures on Travis.

cargo-fuzz is broken on Travis, but the mode is still useful for
those running ./.test_like_travis.rb.

.travis.yml

@@ -37,6 +37,11 @@ matrix:
         MODE='build'
     - rust: nightly
       env: MODE='fuzz run' ARGS='packet_parser -- -max_len=1536 -max_total_time=30'
+  allow_failures:
+    # something's screwy with Travis (as usual) and cargo-fuzz dies with a LeakSanitizer error
+    # even when it's successful. Keep this in .travis.yml in case it starts working some day.
+    - rust: nightly
+      env: MODE='fuzz run' ARGS='packet_parser -- -max_len=1536 -max_total_time=30'
 before_script:
   - if [ "$MODE" == "fuzz run" ]; then cargo install cargo-fuzz; fi
 script: