Include two transitive dependencies to work around conflicts

For people installing released shade from pip and then trying to use it
somehow through entrypoints, 1.20.0 is currently broken because of some
transitive dependencies, ordering issues and conflicting exclusion
ranges.

While this is by no means a comprehensive or sustainable solution to the
problem, it does unbreak the end users currently broken and is not
terribly onerous. Both of these additions are tracked in g-r and both
can be removed when the dependencies that pull in conflicting ranges of
things are removed.

Change-Id: I6a4a1ab5ab109f0650873201868e0f1c4d09c564

releasenotes/notes/workaround-transitive-deps-1e7a214f3256b77e.yaml

@@ -0,0 +1,9 @@
+---
+fixes:
+  - Added requests and Babel to the direct dependencies list to work around
+    issues with pip installation, entrypoints and transitive dependencies
+    with conflicting exclusion ranges. Packagers of shade do not need to
+    add these two new requirements to shade's dependency list - they are
+    transitive depends and should be satisfied by the other things in the
+    requirements list. Both will be removed from the list again once the
+    python client libraries that pull them in have been removed.

requirements.txt

@@ -9,6 +9,13 @@ jmespath>=0.9.0 # MIT
 jsonpatch>=1.1 # BSD
 ipaddress>=1.0.7;python_version<'3.3' # PSF
 os-client-config>=1.22.0 # Apache-2.0
+# These two are here to prevent issues with version pin mismatches from our
+# client library transitive depends.
+# Babel can be removed when ironicclient is removed (because of openstackclient
+# transitive depend)
+Babel>=2.3.4,!=2.4.0  # BSD
+# requests can be removed when designateclient is removed
+requests>=2.10.0,!=2.12.2,!=2.13.0  # Apache-2.0
 requestsexceptions>=1.2.0 # Apache-2.0
 six>=1.9.0 # MIT
 futures>=3.0;python_version=='2.7' or python_version=='2.6' # BSD