Install salt-pepper directly from pypi

Change-Id: I7202b4846f9999abaa1ae8c3eb0d8a326869eb99
diff --git a/src/com/mirantis/mk/Python.groovy b/src/com/mirantis/mk/Python.groovy
index 159ab54..6180daf 100644
--- a/src/com/mirantis/mk/Python.groovy
+++ b/src/com/mirantis/mk/Python.groovy
@@ -295,8 +295,8 @@
     def common = new com.mirantis.mk.Common()
 
     // virtualenv setup
-    setupVirtualenv(path, 'python2')
-    runVirtualenvCommand(path, "pip install git+https://github.com/saltstack/pepper.git")
+    requirements = ['salt-pepper']
+    setupVirtualenv(path, 'python2', requirements)
 
     // pepperrc creation
     rcFile = "${path}/pepperrc"