Clean up yacc files in mkcommon, mkhdr.
Add nan to lib9.
Fix memory corruption bugs in 9term.
diff --git a/src/lib9/mkfile b/src/lib9/mkfile
index a34cdc6..3dbd6b4 100644
--- a/src/lib9/mkfile
+++ b/src/lib9/mkfile
@@ -42,6 +42,7 @@
 	main.$O\
 	malloctag.$O\
 	mallocz.$O\
+	nan.$O\
 	needsrcquote.$O\
 	netmkaddr.$O\
 	notify.$O\