into gc directory, where it gets included as ../gc/ldbody
this is similar to the assemblers including ../cc/lexbody
and ../cc/macbody.

* hook go-specific loader code into 8l.

* make current 8.out.h and 6.out.h backward compatible
with plan 9's versions.  i had added some constants in
the middle of enums and have now moved them to the end.
this keeps us from invalidating old .8 and .6 files.
not sure how much it really matters, but easy to do.

R=r
DELTA=1314  (667 added, 623 deleted, 24 changed)
OCL=26938
CL=26941