Adding oom/offline-installer submodule for casablanca branch

Issue-ID: DOC-505

Signed-off-by: Ondřej Šmalec <o.smalec@partner.samsung.com>
Change-Id: Iacd53fc97ef206f93c6e407d1a68a7ca0e5ea195
diff --git a/.gitmodules b/.gitmodules
index 89b53d4..428ea01 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -373,3 +373,7 @@
 	url = ../oparent/cia
 	branch = .
 	ignore = dirty
+[submodule "docs/submodules/oom/offline-installer.git"]
+	path = docs/submodules/oom/offline-installer.git
+	url = ../oom/offline-installer
+	branch = casablanca