Adds test for Floating Ips bulk Nova V2 API

This patch adds the test for following Nova V2 APIs-
- Create Floating Ips bulk
- Delete Floating Ips bulk
- List Floating Ips bulk

This patch also adds the config option for unallocated
Floating IP Range

Change-Id: I6af52bb2ce2caadf8491740097df71d041643e78
diff --git a/etc/tempest.conf.sample b/etc/tempest.conf.sample
index 37d4d53..918e43c 100644
--- a/etc/tempest.conf.sample
+++ b/etc/tempest.conf.sample
@@ -327,6 +327,11 @@
 # (integer value)
 #shelved_offload_time=0
 
+# Unallocated floating IP range, which will be used to test
+# the floating IP bulk feature for CRUD operation. (string
+# value)
+#floating_ip_range=10.0.0.0/29
+
 # Allows test cases to create/destroy tenants and users. This
 # option enables isolated test cases and better parallel
 # execution, but also requires that OpenStack Identity API