Auto generate vim docs

doc/symbols-outline.txt

@@ -114,6 +114,15 @@ Default values are shown:
       outline_window = {
         -- Where to open the split window: right/left
         position = 'right',
+        -- Only in this fork:
+        -- The default split commands used are 'topleft vs' and 'botright vs'
+        -- depending on `position`. You can change this by providing your own
+        -- `split_command`.
+        -- `position` will not be considered if `split_command` is non-nil.
+        -- This should be a valid vim command used for opening the split for the
+        -- outline window. Eg, 'rightbelow vsplit'.
+        split_command = nil,
+    
         -- Percentage or integer of columns
         width = 25, 
         -- Whether width is relative to the total width of nvim
@@ -495,6 +504,8 @@ TIPS                                                    *symbols-outline-tips*
     3. Icons table
     A fallback is always used if the previous candidate returned either an empty
     string or a falsey value.
+- You can customize the split command used for creating the outline window split
+    using `outline_window.split_command`, such as `"topleft vsp"`. See |windows|
 
 
 RECIPES                                              *symbols-outline-recipes*