vim:plugins: Update coc.nvim to v0.0.82

Update the copied parts from the suggested config in the README.

.config/vim/vimrc.d/25-coc.vim

@@ -1,38 +1,32 @@
 " Primarly taken from:
-" https://github.com/neoclide/coc.nvim/tree/c3d31ad09d#example-vim-configuration
-
-" TextEdit might fail if hidden is not set.
-set hidden
+" https://github.com/neoclide/coc.nvim/tree/v0.0.82#example-vim-configuration
 
 " Some servers have issues with backup files, see #649.
 set nobackup
 set nowritebackup
 
-" Give more space for displaying messages.
-set cmdheight=2
-
-" Don't pass messages to |ins-completion-menu|.
-set shortmess+=c
+" Having longer updatetime (default is 4000 ms = 4 s) leads to noticeable
+" delays and poor user experience.
+set updatetime=300
 
 " Always show the signcolumn, otherwise it would shift the text each time
 " diagnostics appear/become resolved.
-if has("patch-8.1.1564")
-	" Recently vim can merge signcolumn and number column into one
-	set signcolumn=number
-else
 set signcolumn=yes
-endif
+
+"Use <C-n> and <C-p> for navigate completion list like built in completion.
+inoremap <silent><expr> <C-n> coc#pum#visible() ? coc#pum#next(1) : "\<C-n>"
+inoremap <silent><expr> <C-p> coc#pum#visible() ? coc#pum#prev(1) : "\<C-n>"
 
 " Use tab for trigger completion with characters ahead and navigate.
 " NOTE: Use command ':verbose imap <tab>' to make sure tab is not mapped by
 " other plugin before putting this into your config.
 inoremap <silent><expr> <TAB>
-	\ pumvisible() ? "\<C-n>" :
-	\ <SID>check_back_space() ? "\<TAB>" :
+      \ coc#pum#visible() ? coc#pum#next(1):
+      \ <SID>CheckBackspace() ? "\<Tab>" :
       \ coc#refresh()
-inoremap <expr><S-TAB> pumvisible() ? "\<C-p>" : "\<C-h>"
+inoremap <expr><S-TAB> coc#pum#visible() ? coc#pum#prev(1) : "\<C-h>"
 
-function! s:check_back_space() abort
+function! CheckBackspace() abort
   let col = col('.') - 1
   return !col || getline('.')[col - 1]  =~# '\s'
 endfunction
@@ -44,14 +38,15 @@ else
   inoremap <silent><expr> <c-@> coc#refresh()
 endif
 
-" Use <cr> to confirm completion, `<C-g>u` means break undo chain at current
-" position. Coc only does snippet and additional edit on confirm.
-" <cr> could be remapped by other vim plugin, try `:verbose imap <CR>`.
-if exists('*complete_info')
-	inoremap <expr> <cr> complete_info()["selected"] != "-1" ? "\<C-y>" : "\<C-g>u\<CR>"
-else
-	inoremap <expr> <cr> pumvisible() ? "\<C-y>" : "\<C-g>u\<CR>"
-endif
+" Make <CR> to accept selected completion item or notify coc.nvim to format
+" <C-g>u starts a new undo break, please make your own choice.
+inoremap <silent><expr> <CR> coc#pum#visible() ? coc#pum#confirm()
+                              \: "\<C-g>u\<CR>\<c-r>=coc#on_enter()\<CR>"
+
+" Use `[g` and `]g` to navigate diagnostics
+" Use `:CocDiagnostics` to get all diagnostics of current buffer in location list.
+nmap <silent> [g <Plug>(coc-diagnostic-prev)
+nmap <silent> ]g <Plug>(coc-diagnostic-next)
 
 " GoTo code navigation.
 nmap <silent> gd <Plug>(coc-definition)
@@ -60,13 +55,13 @@ nmap <silent> gi <Plug>(coc-implementation)
 nmap <silent> gr <Plug>(coc-references)
 
 " Use K to show documentation in preview window.
-nnoremap <silent> K :call <SID>show_documentation()<CR>
+nnoremap <silent> K :call ShowDocumentation()<CR>
 
-function! s:show_documentation()
-	if (index(['vim','help'], &filetype) >= 0)
-		execute 'h '.expand('<cword>')
+function! ShowDocumentation()
+  if CocAction('hasProvider', 'hover')
+    call CocActionAsync('doHover')
   else
-		call CocAction('doHover')
+    call feedkeys('K', 'in')
   endif
 endfunction
 
@@ -99,4 +94,4 @@ nmap <leader>ac  <Plug>(coc-codeaction)
 nmap <leader>qf  <Plug>(coc-fix-current)
 
 " Add `:Format` command to format current buffer.
-command! -nargs=0 Format :call CocAction('format')
+command! -nargs=0 Format :call CocActionAsync('format')