mockito-all is uberjar which bundles all transitive
deps (hamcrest-core and objenesis) into single jar . This is bad,
becuase it disrupts Maven based dependency management. Projects
using gwtmockito may require different version of
hamcrest-core than the one bundled in mockito-all. That will
result in hamcrest-core classes being twice on classpath
without any guarantee which one will be loaded first. That
leads to very hard to debug issues.