patch 8.1.1280: remarks about functionality not in Vi clutters the help

Problem:    Remarks about functionality not in Vi clutters the help.
Solution:   Move all info about what is new in Vim or already existed in Vi to
            vi_diff.txt.  Remove {not in Vi} remarks. (closes #4268) Add
            "noet" to the help files modeline.  Also include many other help
            file improvements.
diff --git a/runtime/doc/visual.txt b/runtime/doc/visual.txt
index f63a08d..b953dcb 100644
--- a/runtime/doc/visual.txt
+++ b/runtime/doc/visual.txt
@@ -1,4 +1,4 @@
-*visual.txt*    For Vim version 8.1.  Last change: 2019 Feb 25
+*visual.txt*    For Vim version 8.1.  Last change: 2019 May 05
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -20,8 +20,6 @@
 7. Examples				|visual-examples|
 8. Select mode				|Select-mode|
 
-{Vi has no Visual mode, the name "visual" is used for Normal mode, to
-distinguish it from Ex mode}
 {Since Vim 7.4.200 the |+visual| feature is always included}
 
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