dash-wasm -- WebAssembly dash shell for servers and browsers (pre-alpha version

This provides the dash shell compiled to WebAssembly, suitable for use in a
nodejs program or in a web browser. Try this in your browser right now:

LIVE DEMO: https://cowasm.sh

Here is a little demo below, illustrating that Lua, sqlite, tar, and Python 3.11 \(with numpy!\) are all
included, among other things. Do NOT get your hopes up and expect this to work well, since _there are many remaining issues!_

See https://github.com/sagemathinc/cowasm if you're interested in this project, and
in particular the dash package.

``sh
~ $ npx dash-wasm@latest
(CoWasm) sh$ echo $PATH
/cowasm/usr/bin
(CoWasm) sh$ python
Python 3.11.0 (main, Nov 2 2022, 12:26:39) [Clang 15.0.3 (git@github.com:ziglang/zig-bootstrap.git 85033a9aa569b41658404d0e on wasi
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy
>>> numpy.random.rand(2,2)
array([[0.61989363, 0.33999592],
[0.86028145, 0.78855092]])
>>> ^D
(CoWasm) sh$ ls $PATH
basename cut false join mktemp realpath sqlite3 tsort xargs
bzip2 date find less mv rm stat tty yes
cat dirname fmt ln nl rmdir tail uname
chmod du fold logname paste rogue tar unexpand
clear env grep ls pathchk seq tee uniq
comm expand hanoi lua pr sh test viz
cp expr head man python sleep touch wc
csplit factor id mkdir readlink sort tr which
(CoWasm) sh$ lua
Lua 5.4.4 Copyright (C) 1994-2022 Lua.org, PUC-Rio
> 2 + 3
5
> ^D
(CoWasm) sh$ sqlite3
SQLite version 3.39.4 2022-09-29 15:55:41
Enter ".help" for usage hints.
Connected to a transient in-memory database.
Use ".open FILENAME" to reopen on a persistent database.
sqlite> select 2+3;
5
sqlite> ^D
(CoWasm) sh$ echo $((2+3))
5
(CoWasm) sh$ rogue
...
You hit. Defeated the kobold
-------
|.....+############ ---------------------
|.....| # |...........*.......+
-----+- ##+........]..........|
# ---------------------
######
#
---@---
|..*B.|
|.....+
|.....|
|.....|
-+-----
(CoWasm) sh$ stat $PATH/tar
0 62 ---------- 1 (0) (0) 0 743701 "Oct 29 17:19:15 2022" "Oct 29 17:19:15 2022" "Oct 29 17:19:15 2022" 0 0 /cowasm/bin/tar
(CoWasm) sh$ tar --help
tar(bsdtar): manipulate archive files
First option must be a mode specifier:
-c Create -r Add/Replace -t List -u Update -x Extract
Common Options:
-b # Use # 512-byte records per I/O block
-f Location of archive (default /dev/tape)
-v Verbose
-w Interactive
Create: tar -c [options] [ |