Certificate addition support to mon and ro charms

This commit adds the `certificates` config in both RO and MON charms.

Changes:
 - Add `certificates` config option in mon and ro charms
 - Use charmed-osm/ops-lib-charmed-osm library in all charms

Change-Id: I14e3cf7ad2c846c4a2af57f317d4151119ce5fbb
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/mon/config.yaml b/installers/charm/mon/config.yaml
index 5391497..f6d1ae1 100644
--- a/installers/charm/mon/config.yaml
+++ b/installers/charm/mon/config.yaml
@@ -76,3 +76,11 @@
     description: MON will use Keystone backend
     type: boolean
     default: false
+  certificates:
+    type: string
+    description: |
+      comma-separated list of <name>:<content> certificates.
+      Where:
+        name: name of the file for the certificate
+        content: base64 content of the certificate
+      The path for the files is /certs.