tools: add progress implementation

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I9da1674d6cbc688efc7bab0e033788d6ee4694f7
diff --git a/tools/interface.hpp b/tools/interface.hpp
index 2c993bf..c613f0e 100644
--- a/tools/interface.hpp
+++ b/tools/interface.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "flags.hpp"
+#include "progress.hpp"
 
 #include <cstdint>
 #include <string>