Bump DropWizard version to work with JDK 9

[pbailis]

When I run with JDK 9:

jpbailis@suna:$ java -version
java version "9.0.1"
Java(TM) SE Runtime Environment (build 9.0.1+11)
Java HotSpot(TM) 64-Bit Server VM (build 9.0.1+11, mixed mode)
pbailis@suna:$ bin/frontend.sh 
+ java -Xms512m -Xmx7G -cp 'legacy/target/classes:frontend/target/classes:frontend/src/main/resources/:contrib/target/classes:assembly/target/*:' macrobase.runtime.MacroBaseServer server conf/macrobase.yaml
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
    at org.hibernate.validator.internal.util.Version.getJavaRelease(Version.java:36)
    at org.hibernate.validator.internal.engine.ConfigurationImpl.<init>(ConfigurationImpl.java:120)
    at org.hibernate.validator.internal.engine.ConfigurationImpl.<init>(ConfigurationImpl.java:106)
    at org.hibernate.validator.HibernateValidator.createSpecializedConfiguration(HibernateValidator.java:27)
    at org.hibernate.validator.HibernateValidator.createSpecializedConfiguration(HibernateValidator.java:24)
    at javax.validation.Validation$ProviderSpecificBootstrapImpl.configure(Validation.java:220)
    at io.dropwizard.validation.BaseValidator.newConfiguration(BaseValidator.java:28)
    at io.dropwizard.jersey.validation.Validators.newConfiguration(Validators.java:35)
    at io.dropwizard.jersey.validation.Validators.newValidatorFactory(Validators.java:27)
    at io.dropwizard.setup.Bootstrap.<init>(Bootstrap.java:68)
    at io.dropwizard.Application.run(Application.java:72)
    at macrobase.runtime.MacroBaseServer.main(MacroBaseServer.java:22)

Upgrading Dropwizard (dropwizard.version) in pom.xml to 1.2.3 solves this but there are some compatibility issues with current tests.