patch 8.1.2350: other text for CTRL-V in Insert mode with modifyOtherKeys

Problem:    Other text for CTRL-V in Insert mode with modifyOtherKeys.
Solution:   Convert the Escape sequence back to key as if modifyOtherKeys is
            not set, and use CTRL-SHIFT-V to get the Escape sequence itself.
            (closes #5254)
diff --git a/runtime/doc/cmdline.txt b/runtime/doc/cmdline.txt
index 092757a..ab0e682 100644
--- a/runtime/doc/cmdline.txt
+++ b/runtime/doc/cmdline.txt
@@ -77,10 +77,17 @@
 		way as in Insert mode (see above, |i_CTRL-V|).
 		Note: Under Windows CTRL-V is often mapped to paste text.
 		Use CTRL-Q instead then.
+		When |modifyOtherKeys| is enabled then special Escape sequence
+		is converted back to what it was without |modifyOtherKeys|,
+		unless the Shift key is also pressed.
 							*c_CTRL-Q*
 CTRL-Q		Same as CTRL-V.  But with some terminals it is used for
 		control flow, it doesn't work then.
 
+CTRL-SHIFT-V				*c_CTRL-SHIFT-V* *c_CTRL-SHIFT-Q*
+CTRL-SHIFT-Q	Works just like CTRL-V, unless |modifyOtherKeys| is active,
+		then it inserts the Escape sequence for a key with modifiers.
+
 							*c_<Left>* *c_Left*
 <Left>		cursor left
 							*c_<Right>* *c_Right*