Make GWT logging even quieter for Travis build.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79441097

Author: cgdecker

.travis.yml

@@ -4,6 +4,6 @@ jdk:
   - oraclejdk7
   - openjdk7
 
-install: mvn install -U -DskipTests=true -Dgwt.logLevel=INFO
+install: mvn install -U -DskipTests=true -Dgwt.logLevel=WARN
 
-script: mvn verify -U -Dmaven.javadoc.skip=true -Dgwt.logLevel=INFO
+script: mvn verify -U -Dmaven.javadoc.skip=true -Dgwt.logLevel=WARN