Add a WIKI article about The Traditional Vi editor in ~club

About a year ago, The Traditional Vi was installed in Tilde.Club:
<https://ex-vi.sourceforge.net/> .  This patch adds a WIKI article about
this editor, and particularly about using it on the club's premises.

wiki/source/vi.md

@@ -0,0 +1,77 @@
+---
+title: The Vi Editor
+category: software
+author:
+  - ant
+---
+
+*Tilde.Club* has
+[The Traditional Vi](https://ex-vi.sourceforge.net/)
+installed on its premises.
+It is not just another
+[Vi clone](https://texteditors.org/cgi-bin/wiki.pl?ViFamily),
+but the direct continuation
+of Bill Joy's legendary work at Berkeley.
+The binaries are in `/usr/archaic/bin/`
+and the man pages
+(separately for `ex` and `vi`)
+in `/usr/archaic/share/man/man/`.
+
+You can invoke *The Traditional Vi* in several ways
+(in the order of increased engagement):
+
+1. by the full path to the executable:
+
+       /usr/archaic/bin/vi
+
+2. by adding it as an alias to your shell's `rc` file
+   (`~/.bashrc` for *Bash*), e.g:
+
+       alias tvi=/usr/archaic/bin/vi
+
+   and then invokng *Vi* by typing `tvi`,
+
+3. by adding the locations *Vi* and its documentation
+   in front of the `PATH` and `MANPATH` environment variables
+   in your shell's profile script
+   (for *Bash*, `~/.bash_profile` or `~/.profile`):
+
+       export    PATH="/usr/archaic/bin/:$PATH"
+       export MANPATH="/usr/archaic/share/man/man:$MANPATH"
+
+The latter method has the advantage
+of affecting subshells,
+so that if you specify `vi` as the default editor
+in your e-mail or news client, or another CLI program,
+it will invoke *The Traditional Vi*,
+ditto for your shell scripts
+and the `EDITOR` environment variale.
+
+## Resources
+
+1. Bill Joy's
+   [An Introduction to Display Editing with Vi ](https://ex-vi.sourceforge.net/viin/paper.html),
+2. [`vi(1)`](https://ex-vi.sourceforge.net/vi.html) man page,
+3. [`ex(1)`](https://ex-vi.sourceforge.net/ex.html) man page,
+4. [A concise `vi` reference](http://www.ungerhu.com/jxh/vi.html),
+5. [The Ultimate guide to the VI and EX text editors](https://archive.org/details/ultimateguidetov0000unse_i5e4) (a paper book),
+6. The `#vi` channel on the
+   [Libera.Chat](https://libera.chat/)
+   IRC network,
+   dedicated to the original *Vi*
+   and all its variants except *Vim* & co,
+7. [VI experience in the shell](https://deut-erium.github.io/2024/01/28/inputrc.html).
+
+## Building
+
+*The Traditional Vi* is surprisingly easy to build from
+[its source](https://sourceforge.net/p/ex-vi/code/).
+You only need to locate the following line in `Makefile`:
+
+    TERMLIB = termlib
+
+and replace the value with `curses` or `ncurses`,
+depending on your preferred terminal library.
+Now you can build and install the project with:
+
+    make && make install