Add comment regarding wrapping of -to-nix exes (#208)

Author: angerman

nix-tools/default.nix

@@ -47,6 +47,8 @@ in
     name = "nix-tools";
     paths = builtins.attrValues hsPkgs.nix-tools.components.exes;
     buildInputs = [ makeWrapper ];
+    # We wrap the -to-nix executables with the executables from `tools` (e.g. nix-prefetch-git)
+    # so that consumers of `nix-tools` won't have to provide those tools.
     postBuild = ''
       for prog in stack-to-nix cabal-to-nix plan-to-nix; do
         wrapProgram "$out/bin/$prog" --prefix PATH : "${lib.makeBinPath tools}"