Use Jmockit in the JSon marshaller tests

Also use a tool to compare JSon json output to fixtures
Use jmockit in Dsn tests
Automatically detect the InitialContextFactory
Use jmockit for HttpEventBuilderHelper tests
Rewrite SentryHandler tests to use jmockit
Add the Thread-ID to extra details with JUL
Replace mockito with Jmockit when possible