Create scenario tests for load balancers

This patch implements the tempest plugin for
for testing load balancer creation in Octavia.

Co-Authored-By: Jude Cross <jcross@godaddy.com>
Co-Authored-By: Lingxian Kong <anlin.kong@gmail.com>

Depends-On: https://review.openstack.org/557856
Change-Id: I57064f8e0834efba8859a780394a1c69851cc917
diff --git a/.gitignore b/.gitignore
index 963e589..890fe27 100644
--- a/.gitignore
+++ b/.gitignore
@@ -44,6 +44,7 @@
 
 # Sphinx
 doc/build
+doc/source/_build
 
 # pbr generates these
 AUTHORS
@@ -55,4 +56,7 @@
 .*sw?
 
 # Files created by releasenotes build
-releasenotes/build
\ No newline at end of file
+releasenotes/build
+
+# Oslo config generator
+etc/octavia.tempest.conf.sample