• Move jaeger-thrift shadow jar to its own classifier (#526, @jpkrohling)
• Mark gson field in HttpSamplingManager as ignored for toString (#528, @jpkrohling)
• Use abstract factory pattern to allow subclassing core Jaeger types (#509, @isaachier)
• Use SenderFactory classloader for ServiceLoader (#523, @dbuchhorn)
• Reduce visibility of TextMapCodec.contextFromString to package scope (#519, @isaachier)
• Move contextFromString out of JaegerSpanContext into TextMapCodec (#517, @isaachier)