Update xos-tosca to use nose2 for testing

Change-Id: I74575310d3611f75da22532f668437c302cf4a29
diff --git a/.gitignore b/.gitignore
index afc1bc2..24478e5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,7 +5,8 @@
 src/tosca/tmp.yaml
 src/grpc_client/KEYS.py
 
-# Test Coverage
+# Test output
+nose2-junit.xml
 .coverage
 cover
 coverage.xml