patch 8.2.0122: readme files still mention MS-DOS

Problem:    Readme files still mention MS-DOS.
Solution:   Update readme files. (Ken Takata, closes #5486)
diff --git a/READMEdir/README_dos.txt b/READMEdir/README_dos.txt
index 260dbee..3f08612 100644
--- a/READMEdir/README_dos.txt
+++ b/READMEdir/README_dos.txt
@@ -1,6 +1,6 @@
 README_dos.txt for version 8.2 of Vim: Vi IMproved.
 
-This file explains the installation of Vim on MS-DOS and MS-Windows systems.
+This file explains the installation of Vim on MS-Windows systems.
 See "README.txt" for general information about Vim.
 
 There are two ways to install Vim:
@@ -64,10 +64,6 @@
    to another location.  That is where they will stay, the install program
    won't move or copy the runtime files.
 
-   Only for the 32 bit DOS version on MS-DOS without DPMI support (trying to
-   run install.exe will produce an error message): Unpack the CSDPMI4B.ZIP
-   archive and follow the instructions in the documentation.
-
 3. Change to the new directory:
 	cd vim\vim82
    Run the "install.exe" program.  It will ask you a number of questions about
@@ -121,7 +117,7 @@
 	set VIM=d:\editors\vim
 
 - If you have told the "install.exe" program to add the "Edit with Vim" menu
-  entry, you can remove it by running the "uninstal.exe".  See
+  entry, you can remove it by running the "uninstall.exe".  See
   ":help win32-popup-menu".
 
 - In Windows 95/98/NT you can create a shortcut to Vim.  This works for all
@@ -150,5 +146,4 @@
 
 For further information, type one of these inside Vim:
 	:help dos
-	:help msdos
 	:help win32
diff --git a/READMEdir/README_srcdos.txt b/READMEdir/README_srcdos.txt
index 2904fda..ca016bd 100644
--- a/READMEdir/README_srcdos.txt
+++ b/READMEdir/README_srcdos.txt
@@ -1,12 +1,12 @@
 README_srcdos.txt for version 8.2 of Vim: Vi IMproved.
 
 See "README.txt" for general information about Vim.
-See "README_dos.txt" for installation instructions for MS-DOS and MS-Windows.
+See "README_dos.txt" for installation instructions for MS-Windows.
 These files are in the runtime archive (vim82rt.zip).
 
 
-The DOS source archive contains the files needed to compile Vim on MS-DOS or
-MS-Windows.  It is packed for DOS systems, with CR-LF.  It also includes the
-VisVim sources.
+The DOS source archive contains the files needed to compile Vim on MS-Windows.
+It is packed for MS-Windows systems, with CR-LF.  It also includes the VisVim
+sources.
 
 See "src/INSTALLpc.txt" for instructions on how to compile Vim on the PC.
diff --git a/READMEdir/README_w32s.txt b/READMEdir/README_w32s.txt
index 9bf0a67..742a655 100644
--- a/READMEdir/README_w32s.txt
+++ b/READMEdir/README_w32s.txt
@@ -1,15 +1,6 @@
 README_w32s.txt for version 8.2 of Vim: Vi IMproved.
 
-This archive contains the gvim.exe that was specifically compiled for use in
-the Win32s subsystem in MS-Windows 3.1 and 3.11.
-
-Also see the README_bindos.txt, README_dos.txt and README.txt files.
-
-Be careful not to overwrite the Win32s gvim.exe with the another gvim.exe when
-unpacking another binary archive!  Check the output of ":version":
-	Win32s - "MS-Windows 16/32 bit GUI version"
-	 Win32 - "MS-Windows 32 bit GUI version"
-Win32 with OLE - "MS-Windows 32 bit GUI version with OLE support"
-
-For further information, type this inside Vim:
-	:help win32s
+This file used to explain the installation of Vim on MS-Windows 3.1 and 3.11
+systems.  However, support for MS-Windows 3.1 and 3.11 has been removed in
+patch 7.4.1364.
+See "README.txt" for general information about Vim.