Remove old v3 volume services library and use lib/service for v3

Moving volume v3 folders to /lib/services/volumes
Remove old left overs from service/volumes.

The patch removes services/volume api code
Tempest volume api will run from /lib/service

Change-Id: I76fec9c42ecb7038f01a186f3eb51bb471b1679d
diff --git a/releasenotes/notes/move-cinder-v3-to-lib-service-be3ba0c20753b594.yaml b/releasenotes/notes/move-cinder-v3-to-lib-service-be3ba0c20753b594.yaml
new file mode 100644
index 0000000..9223ba5
--- /dev/null
+++ b/releasenotes/notes/move-cinder-v3-to-lib-service-be3ba0c20753b594.yaml
@@ -0,0 +1,7 @@
+features:
+  - |
+    Define the Volume v3 service clients as library interfaces,
+    allowing other projects to use these modules as stable
+    libraries without maintenance changes.
+
+    * messages_client(v3)