git: Add commit template

In order to use the commit template, run the
following command:
git config commit.template .git-commit-template

Reviewed-By: Martin Basti <mbasti@redhat.com>
Reviewed-By: Jan Cholasta <jcholast@redhat.com>
Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>

.git-commit-template

@@ -0,0 +1,5 @@
+component: Subject
+
+Explanation
+
+https://fedorahosted.org/freeipa/ticket/XXXX