Remove the notion of "sys*"

- This idea originates from very early in the project and was, at the
  time, a very easy way to categorise things.
- Now, it doesn't really make much sense - it is fairly arbitary, often
  occuring when there is a change in kernel, but not from builder-hex0
  to fiwix, and sysb is in reality completely unnecessary.
- In short, the sys* stuff is a bit of a mess that makes the project
  more difficult to understand.
- This puts everything down into one folder and has a manifest file that
  is used to generate the build scripts on the fly rather than using
  coded scripts.
- This is created in the "seed" stage.

stage0-posix -- (calls) --> seed -- (generates) --> main steps

Alongside this change there are a variety of other smaller fixups to the
general structure of the live-bootstrap rootfs.

- Creating a rootfs has become much simpler and is defined as code in
  go.sh. The new structure, for an about-to-be booted system, is

/
-- /steps (direct copy of steps/)
-- /distfiles (direct copy of distfiles/)
-- all files from seed/*
-- all files from seed/stage0-posix/*

- There is no longer such a thing as /usr/include/musl, this didn't
  really make any sense, as musl is the final libc used. Rather, to
  separate musl and mes, we have /usr/include/mes, which is much easier
  to work with.
- This also makes mes easier to blow away later.
- A few things that weren't properly in packages have been changed;
  checksum-transcriber, simple-patch, kexec-fiwix have all been given
  fully qualified package names.
- Highly breaking change, scripts now exist in their package directory
  but NOT WITH THE packagename.sh. Rather, they use pass1.sh, pass2.sh,
  etc. This avoids manual definition of passes.
  - Ditto with patches; default directory is patches, but then any patch
    series specific to a pass are named patches-passX.

steps/bison-3.4.2/patches/our-bison.patch

@@ -0,0 +1,18 @@
+SPDX-FileCopyrightText: 2021 fosslinux <fosslinux@aussies.space>
+
+SPDX-License-Identifier: GPL-3.0-or-later
+
+Why do they insist on using themselves to bootstrap themselves? It doesn't
+exist...
+
+--- Makefile.am	2021-04-15 21:29:36.596205032 +1000
++++ Makefile.am	2021-04-15 21:30:00.367365897 +1000
+@@ -39,7 +39,7 @@
+ ## Running the bison from this tarball.  To generate our own parser,
+ ## but also to run the tests.  Of course, you ought to keep a sane
+ ## version of Bison nearby...
+-BISON = $(top_builddir)/tests/bison
++BISON = /usr/bin/bison
+ BISON_IN = $(top_srcdir)/tests/bison.in
+ YACC = $(BISON) -o y.tab.c
+ AM_YFLAGS_WITH_LINES = --defines -Werror -Wall --report=all