Remove webob requirements cap

Looking at the library, and openstack requirements, there doesn't
appear to be a reason to cap webob. So, remove the cap so we can use
newer versions.

Change-Id: Id19c297b540e9081bcf733dff3a334a4b0f477d8
Signed-off-by: Paul Belanger <pabelanger@redhat.com>
diff --git a/requirements.txt b/requirements.txt
index 6318a59..02f17f5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@
 argparse
 PyYAML>=3.1.0
 Paste
-WebOb>=1.2.3,<1.3
+WebOb>=1.2.3
 paramiko>=1.8.0
 GitPython>=0.3.3
 ordereddict