cli/sed: Very basic stream editing of traces.

Extremely limited, but have to start from somewhere.
diff --git a/cli/cli.hpp b/cli/cli.hpp
index c35cb3a..088f0e8 100644
--- a/cli/cli.hpp
+++ b/cli/cli.hpp
@@ -48,6 +48,7 @@
 extern const Command pickle_command;
 extern const Command repack_command;
 extern const Command retrace_command;
+extern const Command sed_command;
 extern const Command trace_command;
 extern const Command trim_command;