Add initial beginning to the gitflow subcommand infrastructure.
diff --git a/gitflow-sh-setup b/gitflow-sh-setup
new file mode 100755
index 0000000..462a183
--- /dev/null
+++ b/gitflow-sh-setup
@@ -0,0 +1,6 @@
+#!/bin/sh
+
+gitflow_check_clean_working_tree() {
+	echo "Working tree $(pwd) clean."
+}
+