Add "make defconfig".  Modify global options to start with CONFIG_TOYBOX_.
diff --git a/Makefile b/Makefile
index c366b13..471c089 100644
--- a/Makefile
+++ b/Makefile
@@ -12,6 +12,10 @@
 
 include kconfig/Makefile
 
+# defconfig is the "maximum sane config"; allyesconfig minus debugging and such.
+defconfig: allyesconfig
+	@sed -i -r -e "s/^(CONFIG_(TOYBOX_DEBUG|TOYBOX_FREE))=.*/# \1 is not set/" .config
+
 .config: Config.in toys/Config.in
 
 # The long and roundabout sed is to make old versions of sed happy.  New ones