Configure default syntax bloquote marker to include :: (issue #1279)

autoload/vimwiki/vars.vim

@@ -676,6 +676,7 @@ function! s:get_default_syntaxlocal() abort
   " type, default, min, max, possible_values, min_length
 
   return extend(s:get_common_syntaxlocal(), {
+        \ 'blockquote_markers': {'type': type([]), 'default': ['>', '::']},
         \ 'bold_match': {'type': type(''), 'default': '\%(^\|\s\|[[:punct:]]\)\@<=\*__Text__\*\%([[:punct:]]\|\s\|$\)\@='},
         \ 'bold_search': {'type': type(''), 'default': '\%(^\|\s\|[[:punct:]]\)\@<=\*\zs\%([^*`[:space:]][^*`]*[^*`[:space:]]\|[^*`[:space:]]\)\ze\*\%([[:punct:]]\|\s\|$\)\@='},
         \ 'bullet_types': {'type': type([]), 'default': ['-', '*', '#']},

test/issue_1279_gq_wrap_definition.vader

@@ -8,8 +8,18 @@ Given vimwiki (Dummy heading):
 Do (gqq):
   gqq
 
-Expect (Heading6):
+Expect (Wrapped with the :: prefix prepended):
   :: aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa
   :: aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa
   :: aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa aaa
   :: aaa aaa aaa
+
+Given vimwiki (Small heading):
+  :: aaa
+
+Do (A <CR>):
+  A\<CR>
+
+Expect (Bloquote prefix :: inserted):
+  :: aaa
+  ::