honor ZUUL_UUID where UUID is used

The addition of ZUUL_COMMIT (commit 81515ad, change I88c38a28)
deprecated the UUID parameter in favor of ZUUL_UUID but did not honor
the new parameter.

This patch add ZUUL_UUID lookup in jenkins_endpoint() and
findBuildInQueue() with a fallback on UUID. Probably only needed on
jenkins_endpoint() when a Jenkins job lack the UUID parameter, but I
think we might as well add it in findBuildInQueue() just to be safe.

Also update the documentation to uses ZUUL_ prefixed variables where
relevant and added a note about GERRIT_PROJECT and UUID being
deprecated.

Change-Id: Ie0426f388cbd3a373af2110b7460aca6ff4f1751
Reviewed-on: https://review.openstack.org/14327
Reviewed-by: James E. Blair <corvus@inaugust.com>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins
diff --git a/doc/source/launchers.rst b/doc/source/launchers.rst
index eb8cd10..70b1455 100644
--- a/doc/source/launchers.rst
+++ b/doc/source/launchers.rst
@@ -70,11 +70,17 @@
 **ZUUL_COMMIT**
   The commit SHA1 at the head of ZUUL_REF
 
-Those are the only required parameters.  The UUID is needed for Zuul
-to keep track of the build, and the REF and COMMIT parameters are for
-use in preparing the git repo for the build.  The following parameters
-will be sent for all builds, but are not required so you do not need
-to configure Jenkins to accept them if you do not plan on using them:
+Those are the only required parameters.  The ZUUL_UUID is needed for Zuul to
+keep track of the build, and the ZUUL_REF and ZUUL_COMMIT parameters are for
+use in preparing the git repo for the build.
+
+.. note::
+    The GERRIT_PROJECT and UUID parameters are deprecated respectively in
+    favor of ZUUL_PROJECT and ZUUL_UUID.
+
+The following parameters will be sent for all builds, but are not required so
+you do not need to configure Jenkins to accept them if you do not plan on using
+them:
 
 **ZUUL_PROJECT**
   The project that triggered this build