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/fold.txt b/runtime/doc/fold.txt
index c3ee97e..fb62d28 100644
--- a/runtime/doc/fold.txt
+++ b/runtime/doc/fold.txt
@@ -1,4 +1,4 @@
-*fold.txt*      For Vim version 8.1.  Last change: 2017 Mar 18
+*fold.txt*      For Vim version 8.1.  Last change: 2019 May 05
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -14,7 +14,6 @@
 3. Fold options		|fold-options|
 4. Behavior of folds	|fold-behavior|
 
-{Vi has no Folding}
 {not available when compiled without the |+folding| feature}
 
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