Fix git checkout

If the branch does not exist locally, create it properly.
Otherwise the script will abort with freshly checkout sources.

Change-Id: I05960ed862fa61f3c9435f6749d941128812887b

autogenerate_config_docs/autohelp-wrapper

@@ -154,7 +154,12 @@ if [ "$FAST" -eq 0 ] ; then
 
         (
             cd $SOURCESDIR/$project
-            git checkout $BRANCH
+            GIT_CMD="git show-ref --verify --quiet refs/heads/$BRANCH"
+            if $GIT_CMD; then
+                git checkout $BRANCH
+            else
+                git checkout -b $BRANCH remotes/origin/$BRANCH
+            fi
             python setup.py install
         )
     done