Don't use <Plug> definitions for VimwikiReturn mappings.

This is necessary to properly allow the user to remap these since there
are different arguments to the command. The documentation regarding this
command was also updated to be more clear.

doc/vimwiki.txt

@@ -620,7 +620,6 @@ LIST MAPPINGS, INSERT MODE                             *vimwiki-list-mappings*
                         useful to end a list, simply press <CR> twice.
                         See |vimwiki-lists| for details and for how to
                         configure the behavior.
-                        Remap command: `<Plug>VimwikiReturn15`
 
                                                             *vimwiki_i_<S-CR>*
 <S-CR>                  Does not insert a new list item, useful to create
@@ -628,7 +627,6 @@ LIST MAPPINGS, INSERT MODE                             *vimwiki-list-mappings*
                         details and for how to configure the behavior. The
                         default map may not work in all terminals and may
                         need to be remapped.
-                        Remap command: `<Plug>VimwikiReturn22`
 
                                                              *vimwiki_i_<C-T>*
 <C-T>                   Increase the level of a list item.
@@ -1619,20 +1617,26 @@ used.
 
 While writing lists, the keys <CR>, o and O insert new bullets or numbers as
 you would expect it. A new bullet/number is inserted if and only if the cursor
-is in a list item. To make a list item with more than one line, press <S-CR>
-or press <CR> and <C-L><C-M>.
+is in a list item. If you use hard line wraps within your lists then you will
+need to remap `<CR>` to `VimwikiReturn 3 5`, use <S-CR>, or press <CR> and
+<C-L><C-M>.
+
 Note that the mapping <S-CR> is not available in all terminals.
 
 Furthermore, <CR> and <S-CR> behave differently when the cursor is behind an
 empty list item. See the table below.
 
-To remap the default behavior: >
-  :imap <Leader>e <Plug>VimwikiReturn15
-  :imap <Leader>r <Plug>VimwikiReturn22
+To customize the behavior you should use an autocmd or place the mappings in
+`~/.vim/after/ftplugin/vimwiki.vim`. This is necessary to avoid an error that
+the command `VimwikiReturn` doesn't exist when editing non Vimwiki files.: >
 
-To customize the behavior: >
-  inoremap <CR> <Esc>:VimwikiReturn 1 1<CR>
-  inoremap <S-CR> <Esc>:VimwikiReturn 3 5<CR>
+  autocmd FileType vimwiki inoremap <silent><buffer> <CR>
+              \ <C-]><Esc>:VimwikiReturn 3 5<CR>
+  autocmd FileType vimwiki inoremap <silent><buffer> <S-CR>
+              \ <Esc>:VimwikiReturn 2 2<CR>
+
+Note: Prefixing the mapping with `<C-]>` expands iabbrev definitions and
+requires Vim > 7.3.489.
 
 The first argument of the command :VimwikiReturn is a number that specifies
 when to insert a new bullet/number and when not, depending on whether the

ftplugin/vimwiki.vim

@@ -438,16 +438,6 @@ nnoremap <silent><buffer> <Plug>VimwikiListo
     \ :<C-U>call vimwiki#lst#kbd_o()<CR>
 nnoremap <silent><buffer> <Plug>VimwikiListO
     \ :<C-U>call vimwiki#lst#kbd_O()<CR>
-if has('patch-7.3.489')
-  " expand iabbrev on enter
-  inoremap <silent><buffer> <Plug>VimwikiReturn15
-      \ <C-]><Esc>:VimwikiReturn 1 5<CR>
-else
-  inoremap <silent><buffer> <Plug>VimwikiReturn15
-    \ <Esc>:VimwikiReturn 1 5<CR>
-endif
-inoremap <silent><buffer> <Plug>VimwikiReturn22
-    \ <Esc>:VimwikiReturn 2 2<CR>
 
 " default lists key mappings
 if str2nr(vimwiki#vars#get_global('key_mappings').lists)
@@ -482,8 +472,19 @@ if str2nr(vimwiki#vars#get_global('key_mappings').lists)
   call vimwiki#u#map_key('n', 'gL', '<Plug>VimwikiRemoveCBInList')
   call vimwiki#u#map_key('n', 'o', '<Plug>VimwikiListo')
   call vimwiki#u#map_key('n', 'O', '<Plug>VimwikiListO')
-  call vimwiki#u#map_key('i', '<CR>', '<Plug>VimwikiReturn15')
-  call vimwiki#u#map_key('i', '<S-CR>', '<Plug>VimwikiReturn22')
+
+  " handle case of existing VimwikiReturn mappings outside the <Plug> definition
+  if maparg('<CR>', 'i') !~# '.*VimwikiReturn*.'
+    if has('patch-7.3.489')
+      " expand iabbrev on enter
+      inoremap <silent><buffer> <CR> <C-]><Esc>:VimwikiReturn 1 5<CR>
+    else
+      inoremap <silent><buffer> <CR> <Esc>:VimwikiReturn 1 5<CR>
+    endif
+  endif
+  if  maparg('<S-CR>', 'i') !~# '.*VimwikiReturn*.'
+    inoremap <silent><buffer> <S-CR> <Esc>:VimwikiReturn 2 2<CR>
+  endif
 
   " change symbol for bulleted lists
   for s:char in vimwiki#vars#get_syntaxlocal('bullet_types')
@@ -521,13 +522,11 @@ if str2nr(vimwiki#vars#get_global('key_mappings').lists)
 endif
 
 function! s:CR(normal, just_mrkr)
-  if str2nr(vimwiki#vars#get_global('key_mappings').table_mappings)
-    let res = vimwiki#tbl#kbd_cr()
-    if res != ""
-      exe "normal! " . res . "\<Right>"
-      startinsert
-      return
-    endif
+  let res = vimwiki#tbl#kbd_cr()
+  if res != ""
+    exe "normal! " . res . "\<Right>"
+    startinsert
+    return
   endif
   call vimwiki#lst#kbd_cr(a:normal, a:just_mrkr)
 endfunction