target: less implicit inclusion of "command.h"

Lots of files still include it, often through needless
duplicate inclusion of "log.h"; sigh.

This cleans up the inclusion graph a bunch, so there are
fewer inclusion paths, but it doesn't change much otherwise.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

src/helper/options.c

@@ -25,7 +25,6 @@
 #endif
 
 #include "configuration.h"
-#include "log.h"
 // @todo the inclusion of server.h here is a layering violation
 #include "server.h"