Investigate and possibly fix the Javadoc warning during the build

[rwanderc]

This warning occurs when building the lib module (at least in java8; not sure if that happens in other versions).

Javadoc Warnings
warning: unknown enum constant When.MAYBE
reason: class file for javax.annotation.meta.When not found

According to this link, it needs a library, but it's not intended to introduce this lib (and eventually force it as a dependency in projects using MultiRabbit) only to fix the Javadoc warning during the build. But also it does not work in test scope.

        <dependency>
            <groupId>com.google.code.findbugs</groupId>
            <artifactId>jsr305</artifactId>
            <version>3.0.2</version>
        </dependency>