Added requirements monitoring file

ECOM-3801

requirements/monitoring/requirements.txt

+# This requirements.txt file is meant to pull in other requirements.txt files so that
+# dependency monitoring tools like gemnasium.com can easily process them.
+
+# It can not be used to do the full installation because it is not in the correct
+# order.
+
+-r ../base.txt
+-r ../docs.txt
+-r ../local.txt
+-r ../optional.txt
+-r ../production.txt
+-r ../test.txt