1\ resolve the bug 655, no trace log will be shown any longer
2\ replace minidom with ETree to parse and generate XML in http_server
Merge the PR https://github.com/testkit/testkit-lite/pull/3 for testing 2.3.0-2
Update the Release number for 2.3.0-2
Updated by WeiDong

   1. change default expect_result from "none" to "0"
   2. add log when split xml by set
   3. update function to remove empty set from the testing list, after split xml by set