move away from deprecated configuration command

nix/home.nix

@@ -117,15 +117,12 @@ in {
     enable = true;
     vimAlias = true;
     withPython = true;
-    configure = {
-      packages.nixBundle = with pkgs.vimPlugins; {
-        start = [
+    plugins = with pkgs.vimPlugins; [
       vim-sensible
       vim-startify
       vim-javascript
       vim-ruby
       vim-nix
-          elm-vim
       vim-elixir
       alchemist-vim
       haskell-vim
@@ -149,9 +146,8 @@ in {
       deoplete-nvim
       papercolor-theme
     ];
-      };
 
-      customRC = ''
+    extraConfig = ''
       filetype plugin indent on
 
       " ALE
@@ -258,7 +254,6 @@ in {
       endif
     '';
   };
-  };
 
   programs.tmux = {
     enable = true;