Make mappings repeatable with . through repeat.vim

Use of repeat.vim is purely optional, but very beneficial for typical commenting uses.

doc/NERD_commenter.txt

@@ -139,6 +139,10 @@ left side (|<Leader>|cl) or both sides (|<Leader>|cb).
 [count]|<Leader>|cu |NERDComUncommentLine|
 Uncomments the selected line(s).
 
+
+With the optional repeat.vim plugin (vimscript #2136), the mappings can also
+be repeated via |.|
+
 ------------------------------------------------------------------------------
 3.2 Functionality details                        *NERDComFunctionalityDetails*
 

plugin/NERD_commenter.vim

@@ -1128,6 +1128,8 @@ function! NERDComment(mode, type) range
     endif
 
     let &ignorecase = oldIgnoreCase
+
+    silent! call repeat#set("\<Plug>NERDCommenter". a:type)
 endfunction
 
 " Function: s:PlaceDelimitersAndInsBetween() function {{{2