Improved compatibility of dd-java-agent co-existing with dd-trace
Internal classes of dd-trace inside dd-java-agent are dynamically modified using shadow. This created a problem with previous versions when dd-trace also existed on the classpath separately. The classloader could find the same classname in multiple different jars, but with different classes. These internal versions of classes from dd-trace now have a different package name and should not cause this conflict.
Fixed NPE in Servlet Context Helpers
If JettyServletHelper or TomcatServletHelper were triggered more than once, or there happened to already be a filter registered with the name tracingFilter, the helper would throw a NullPointerException. This registration process is now properly handled by checking registration first and checking for null before continuing.