tests: Upload junit.xml to AppVeyor.

.appveyor.yml

@@ -14,4 +14,12 @@ install:
   - C:\Python27\python -u scripts\dev\ci_install.py
 
 test_script:
-  - C:\Python34\Scripts\tox -e %TESTENV% -- -p "no:sugar"
+  - C:\Python34\Scripts\tox -e %TESTENV% -- -p "no:sugar" --junitxml=junit.xml
+
+after_test:
+  - ps: |
+      if ($env:TESTENV -ne "pylint") {
+          $url = "https://ci.appveyor.com/api/testresults/junit/$($env:APPVEYOR_JOB_ID)"
+          $file = '.\junit.xml'
+          (New-Object 'System.Net.WebClient').UploadFile($url, (Resolve-Path $file))
+      }