Add built-in types

Not sure why it seems like the 'is-not? local' is not working.

Will investigate later

queries/highlights.scm

@@ -3,6 +3,10 @@
   function: (identifier) @function.builtin)
   (#match? @function.builtin "^(chr|concat|exit|flush|getchar|not|ord|print|print_err|print_int|size|strcmp|streq|substring)$")
   (#is-not? local))
+
+((type_identifier) @type.builtin
+  (#match? @type.builtin "^(int|string)$")
+  (#is-not? local))
 ; }}}
 
 ; Keywords {{{

test/highlight/built-ins.tig

@@ -3,11 +3,23 @@ let
   /*       ^ function.builtin */
 
   primitive exit(ret: int) /* Shadowing the prelude-included built-in */
+  /*                  ^ type.builtin */
 
   var b := exit(0)
   /*       ^ function */
 
+  type int = string /* Shadowing the built-in type */
+  /*         ^ type.builtin */
+
+  var c : int := "This is an \"int\""
+  /*      ^ type.builtin (not sure why it isn't 'type')*/
 in
+  let
+    var c : int := "This is an int"
+    /*      ^ type.builtin (not sure why it isn't 'type')*/
+  in
+  end;
+
   exit(1);
   /* <- function */
 

test/highlight/identifiers.tig

@@ -1,15 +1,15 @@
 type int = int
 /*   ^ variable */
-/*         ^ type */
+/*         ^ type.builtin */
 
 type int_array = array of int
-/*                        ^ type */
+/*                        ^ type.builtin */
 
 type record = {a: int, b: string}
 /*             ^ property */
-/*                ^ type */
+/*                ^ type.builtin */
 /*                     ^ property */
-/*                        ^ type */
+/*                        ^ type.builtin */
 
 var record := record {a = 12, b = "27"}
 /*  ^ variable */
@@ -23,7 +23,7 @@ var array := int_array[12] of 27;
 
 primitive func(a: int, b: string) : array
 /*             ^ variable.parameter */
-/*                ^ type */
+/*                ^ type.builtin */
 /*                     ^ variable.parameter */
-/*                        ^ type */
+/*                        ^ type.builtin */
 /*                                  ^ type */