Install build dependencies before building package

scripts/build.py

@@ -77,6 +77,9 @@ def build_package(repo_dir, package_dir, name,
         for entry in _get_log_entries():
             run_checked(command + [entry])
 
+        command = ["apt-get", "build-dep", name]
+        run_checked(command)
+
         command = ["debuild", "-b", "-uc", "-us"]
         run_checked(command)