Fix job example and misspelling

At some point, we changed 'image' to 'label' and missed that in
the docs. Also correct a misspelled word.

Change-Id: Ie0e6ef8cc9eafe9b5353a07e6d11b6c67580b77a
diff --git a/doc/source/user/jobs.rst b/doc/source/user/jobs.rst
index 577d147..7f1c3cb 100644
--- a/doc/source/user/jobs.rst
+++ b/doc/source/user/jobs.rst
@@ -3,7 +3,7 @@
 Job Content
 ===========
 
-Zuul jobs are implemneted as Ansible playbooks.  Zuul prepares the
+Zuul jobs are implemented as Ansible playbooks.  Zuul prepares the
 repositories used for a job, installs any required Ansible roles, and
 then executes the job's playbooks.  Any setup or artifact collection
 required is the responsibility of the job itself.  While this flexible