Use upper-constraints.txt in tox envs

Change-Id: I99ea43a9d5c849e11f22cc027b7b694dd9d0a7a2

tox.ini

@@ -17,7 +17,7 @@ whitelist_externals = find
                       make
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
-install_command = pip install -U {opts} {packages}
+install_command = pip install -c ./upper-constraints.txt -U {opts} {packages}
 usedevelop = True
 commands =
   find . -type f -name "*.pyc" -delete

upper-constraints.txt

@@ -43,3 +43,13 @@ requests===2.18.4
 six===1.11.0
 SQLAlchemy===1.1.14
 virtualenv===15.1.0
+
+
+# testing
+
+pytest===3.3.0
+pytest-cov===2.5.1
+pytest-forked===0.2
+pytest-html===1.16.0
+pytest-metadata===1.5.1
+pytest-xdist===1.20.1