extract dfa generator to a separate file in repository root, so that it could be reused

shf/fcore.mlb

@@ -3,6 +3,7 @@ $(SML_LIB)/basis/basis.mlb
 (* LIBRARIES (purely functional) *)
 ../brolib-sml/src/line_gap.sml
 ../cozette-sml/fonts-with-z-index/cozette-ascii.mlb
+../dfa-gen/dfa-gen.sml
 
 (* FUNCTIONAL CORE *)
 fcore/bin-search.sml
@@ -10,9 +11,8 @@ fcore/bin-search.sml
 ann
   "allowVectorExps true"
 in
-  fcore/persistent-vector.sml
+  fcore/search-list/persistent-vector.sml
 end
-fcore/search-list/dfa-gen.sml
 fcore/search-list/search-list.sml
 
 message-types/input-msg.sml