appveyor.yml: publish test results (#1368)
appveyor.yml: publish test results (#1368)

- Recent change at AppVeyor parses our NUnit output
- Publishes test NUnit results to the build's Tests tab
- Also:
  * make Configuration a parameter rather than hard wired
  * set DLR_ROOT and DLR_BIN
  * use defaults for email content

Signed-off-by: Tim Orling <eb2619d4329cce55563af4515ea057967b34e6ac@linux.intel.com>
slozier/ironpython2,slozier/ironpython2,slozier/ironpython2,IronLanguages/ironpython2,IronLanguages/ironpython2,slozier/ironpython2,slozier/ironpython2,IronLanguages/ironpython2,IronLanguages/ironpython2,IronLanguages/ironpython2,IronLanguages/ironpython2,IronLanguages/ironpython2,slozier/ironpython2,slozier/ironpython2