Refactor var functions of Pipeline library

Move all named functions under com.mirantis.mcp package

Change-Id: I98002e038173fce2325d069e951b221c61109e69
diff --git a/src/com/mirantis/mcp/Common.groovy b/src/com/mirantis/mcp/Common.groovy
index 847c851..c8c5ea5 100644
--- a/src/com/mirantis/mcp/Common.groovy
+++ b/src/com/mirantis/mcp/Common.groovy
@@ -17,4 +17,16 @@
 def getDatetime(format = "yyyyMMddHHmmss") {
     def now = new Date();
     return now.format(format, TimeZone.getTimeZone('UTC'));
-}
\ No newline at end of file
+}
+
+/**
+ * Run tox with or without specified environment
+ * @param env String, name of environment
+ */
+def runTox(String env = null) {
+  if (env) {
+    sh "tox -v -e ${env}"
+  } else {
+    sh "tox -v"
+  }
+}