migrated to new version of nb.h

builder.c

@@ -0,0 +1,21 @@
+#define NB_IMPLEMENTATION
+#include "nb.h"
+
+int main(int argc, char **argv){
+  nb_rebuild(argc, argv);
+  
+  nb_arr cmd;
+
+  nb_append(&cmd, "gcc");
+  nb_append(&cmd, "-Wall -Wextra");
+  nb_append(&cmd, "lexer.c");
+  nb_append(&cmd, "-o lex");
+  nb_cmd(&cmd); 
+
+
+  nb_append(&cmd, "./lex");
+  for (int i=1; i<argc; ++i){
+    nb_append(&cmd, argv[i]);
+  }
+  nb_cmd(&cmd);
+}