Set the travis CI build to continue even if some tasks failed

The --continue argument makes gradle try and build every task whose dependencies finished successfully. This is in contrast to the "regular" behavior of stopping at the first failure.

This is useful because it will show us all the failed tests (from all test tasks) instead of just the first test task that failed.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=237792667

.travis.yml

@@ -56,4 +56,4 @@ env:
 # output, instead of the default 10.
 # See notes on the CREDZ and REPORT_GCS_BUCKET environment variable in the
 # comments at the top of the file.
-script: cd gradle && echo "$CREDZ" >credz.json && chmod 755 ./gradlew && travis_wait 45 ./gradlew build  -P gcsBucket="$REPORT_GCS_BUCKET" -P gcsCredentialsFile=credz.json -P gcsMultithreadedUpload=yes
+script: cd gradle && echo "$CREDZ" >credz.json && chmod 755 ./gradlew && travis_wait 45 ./gradlew build --continue -P gcsBucket="$REPORT_GCS_BUCKET" -P gcsCredentialsFile=credz.json -P gcsMultithreadedUpload=yes