patch 9.0.0445: when opening/closing window text moves up/down
Problem: When opening/closing window text moves up/down.
Solution: Add the 'splitscroll' option. When off text will keep its
position as much as possible.
diff --git a/runtime/doc/quickref.txt b/runtime/doc/quickref.txt
index 67fc28e..2cc2358 100644
--- a/runtime/doc/quickref.txt
+++ b/runtime/doc/quickref.txt
@@ -919,6 +919,7 @@
'spellsuggest' 'sps' method(s) used to suggest spelling corrections
'splitbelow' 'sb' new window from split is below the current one
'splitright' 'spr' new window is put right of the current one
+'splitscroll' 'spsc' determines scroll behavior when splitting windows
'startofline' 'sol' commands move cursor to first non-blank in line
'statusline' 'stl' custom format for the status line
'suffixes' 'su' suffixes that are ignored with multiple match