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/terminal.txt b/runtime/doc/terminal.txt
index 006422d..d01959b 100644
--- a/runtime/doc/terminal.txt
+++ b/runtime/doc/terminal.txt
@@ -1,4 +1,4 @@
-*terminal.txt*	For Vim version 8.1.  Last change: 2019 Feb 25
+*terminal.txt*	For Vim version 8.1.  Last change: 2019 May 05
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -42,7 +42,6 @@
       Communication			|termdebug-communication|
       Customizing			|termdebug-customizing|
 
-{Vi does not have any of these commands}
 {only available when compiled with the |+terminal| feature}
 The terminal feature requires the |+job| and |+channel| features.