remove unused ntuck generalization, and rewrite napply not to use tuck

basis/generalizations/generalizations-docs.factor

@@ -332,12 +332,6 @@ HELP: nappend-as
 
 { nappend nappend-as } related-words
 
-HELP: ntuck
-{ $values
-     { "n" integer }
-}
-{ $description "A generalization of " { $link tuck } " that can work for any stack depth. The top item will be copied and placed " { $snippet "n" } " items down on the stack." } ;
-
 ARTICLE: "sequence-generalizations" "Generalized sequence operations"
 { $subsections
     narray
@@ -357,7 +351,6 @@ ARTICLE: "shuffle-generalizations" "Generalized shuffle words"
     -nrot
     nnip
     ndrop
-    ntuck
     mnswap
     nweave
 } ;

basis/generalizations/generalizations.factor

@@ -71,9 +71,6 @@ MACRO: ndrop ( n -- )
 MACRO: nnip ( n -- )
     '[ [ _ ndrop ] dip ] ;
 
-MACRO: ntuck ( n -- )
-    2 + '[ dup _ -nrot ] ;
-
 MACRO: ndip ( n -- )
     [ [ dip ] curry ] n*quot [ call ] compose ;
 
@@ -112,8 +109,8 @@ MACRO: cleave* ( n -- )
     [ 1 - [ [ [ keep ] curry ] dip compose ] n*quot [ call ] compose ] 
     if-zero ;
 
-MACRO: napply ( n -- )
-    [ [ drop ] ] dip [ '[ tuck _ 2dip call ] ] times ;
+: napply ( quot n -- )
+    [ dupn ] [ spread* ] bi ; inline
 
 : apply-curry ( ...a quot n -- )
     [ [curry] ] dip napply ; inline