There was an incompatible mix of jackson dependencies which caused the app to not start up. Changed the tracer client to use an old version, but allow the agent to still use a newer version (since it is shadowed).
By default, instrumentation is enabled, and can be disabled by default by overriding the `defaultEnabled` method. Instrumentation can also be disabled individually or enabled when default is disabled.
Java 9 is commented out because there are some test failures that will be investigated later.
Some tests had to be excluded from Java 7 because they don’t have a Java 7 compatible version.