switch to denite and platinum searcher (pt)

.vimrc

@@ -126,6 +126,7 @@ Plug 'whonore/coquille', {'branch': 'pathogen-bundle', 'for': 'coq'}
 Plug 'mhartington/nvim-typescript'
 
 Plug 'sheerun/vim-polyglot'
+Plug 'Shougo/denite.nvim'
 "Plug 'vim-scripts/fish-syntax'
 "Plug 'kchmck/vim-coffee-script'
 "Plug 'rodjek/vim-puppet'
@@ -608,10 +609,14 @@ nnoremap <Leader>ss :SyntasticSetLoclist<CR>
 nnoremap <Leader>fn :lnext<CR>
 " Prev quickfix.
 nnoremap <Leader>fp :lprev<CR>
-" Ack (grep) for the word under the cursor.
-nnoremap <Leader>aw :exe 'Ack ' . expand('<cword>')<CR>
-" Ack prompt.
-nnoremap <Leader>ac :Ack 
+nnoremap <silent> <Leader>aw :<C-u>DeniteCursorWord -buffer-name=search-buffer grep<CR>
+call denite#custom#var('grep', 'command', ['pt'])
+call denite#custom#var('grep', 'default_opts',
+      \ ['--nogroup', '--nocolor', '--smart-case'])
+call denite#custom#var('grep', 'recursive_opts', [])
+call denite#custom#var('grep', 'pattern_opt', [])
+call denite#custom#var('grep', 'separator', ['--'])
+call denite#custom#var('grep', 'final_opts', [])
 " For C++ -- A is a great plugin which allows you to jump from the c file to the
 " header and vice-versa. Mneumonic here is headerheader.
 nnoremap <Leader>hh :A<CR>