* remove dubbo-test-examples and dubbo-test-benchmark
* rename package to org.apache.dubbo
* support old SPI file
* remove final for RpcException and URL
* add debug sysout in UT
* add debug info in UT
* ignore 2 cases temporary
* add finally clear for SHUTDOWN_WAIT_KEY property
* clear SHUTDOWN_WAIT_KEY before test
* add dubbo SPI and interface bridge class
* support EchoService and GenericService
* rename groupId to org.apache.dubbo
* add debug info for UT