Add optional silent install and config of ldap to devstack

Edited initial ldap entries and olcdb template file as recommended by Brant.

Change-Id: I1404cc5c754f878e32a2d10254840d092211e6e6
diff --git a/files/rpms/ldap b/files/rpms/ldap
new file mode 100644
index 0000000..2f7ab5d
--- /dev/null
+++ b/files/rpms/ldap
@@ -0,0 +1,3 @@
+openldap-servers
+openldap-clients
+python-ldap