Adding versions for infra related docker images

1. latest tag replaced by version number for vnc server
2. added specific version for own_nginx image
3. version control improved in ansible roles accordingly

Solves OOM-1766

Issue-ID: OOM-1767

Change-Id: I147c56b46a419188099d8ed3e78fed68810893e2
Signed-off-by: Tomáš Levora <t.levora@partner.samsung.com>
diff --git a/ansible/roles/nexus/defaults/main.yml b/ansible/roles/nexus/defaults/main.yml
index 3776f44..92089e9 100644
--- a/ansible/roles/nexus/defaults/main.yml
+++ b/ansible/roles/nexus/defaults/main.yml
@@ -4,3 +4,5 @@
 # By dafault no additional docker images pushed to nexus at runtime
 # but all images are pre-populated either at buildtime or at install time (populate_nexus).
 runtime_images: {}
+# Default rule for tarball naming translation
+nexus3_image_tar: "{{ nexus3_image | regex_replace('(\\/|\\:)', '_') }}.tar"