Windows: product names, the editors, WSL; the Linux page's image step

Assembled from development commit c3c40f6c8fca. Since 830b193: on Windows the
products carry Windows names (ktext.exe, klammertext.dll, document.dll,
reflect.dll) and the console's output code page is UTF-8 for a run; the
editor tooling works on Windows (VS Code, Sublime Text, Vim, with the
interpreter's name chosen by platform) and Notepad++ joins it
(doc/edit/notepadpp: a User Defined Language and two Run-menu commands);
a sixth install page, doc/install/windows_wsl_install.md, for Linux
inside WSL; the Windows page opens with the three routes and gains its
editor section, the PowerShell quoting and Path notes; the Linux page
installs OpenImageIO from the python3-openimageio package and verifies
with kdiag --machine; the README lists all six install pages. Linux and
macOS behaviour is unchanged.

doc/edit/shared/klammertext_edit.py

@@ -56,7 +56,10 @@ import sys
 # --- policy ----------------------------------------------------------------
 
 # Klammer names whose content is a literal argument (verbatim interior,
-# closed by a named NAME@ delimiter).
+# closed by a named NAME@ delimiter).  The static syntax artifacts restate
+# this set by hand (Emacs defcustom, .sublime-syntax, vim syntax, tmLanguage,
+# the Notepad++ UDL -- which can hold only "code"); doc/edit/README.md,
+# "Keeping things in sync".
 LITERAL_KLAMMERS = set(["code", "c"])
 
 # Klammers that contribute no indentation level (a @document's paragraphs
@@ -1037,6 +1040,13 @@ def _cli(argv):
     if len(argv) < 1:
         return usage()
     mode = argv[0]
+    # Klammertext writes LF on every system.  Python's text-mode stdout turns
+    # every "\n" into "\r\n" on Windows, and an editor -- or the test suite --
+    # comparing the result with an LF buffer then sees every line changed.
+    # stdin keeps universal newlines: a CRLF buffer arrives as "\n" lines,
+    # which is what the algorithms expect.
+    if hasattr(sys.stdout, 'reconfigure'):      # 3.7+; the floor is 3.8
+        sys.stdout.reconfigure(newline='\n')
     s = sys.stdin.read()
 
     if mode == 'indent':