Improved for-in rewriting so as not to require a conditional NULL check in every generated unbox(). Tighened up generated unbox() as a result. Exposed a number of DKT- macros since they might be useful to users. Created and used unbox_attrs to improve inline performance.
Big makefile cleanup. Removed common.mk. Used DEBUG-STMT() in a few places to rid of #if defined DEBUG ... #endif.