doc: massive refactor and simplification to migrate to mkdocs

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

doc/config/runparts.md

@@ -0,0 +1,51 @@
+Run-parts Scripts
+-----------------
+
+**Syntax:** `runparts [progress] [sysv] <DIR>`
+
+Call [run-parts(8)][] on `DIR` to run start scripts.  All executable
+files in the directory are called, in alphabetic order.  The scripts in
+this directory are executed at the very end of runlevel `S`.
+
+A common use-case for runparts scripts is to create and enable/disable
+services, which Finit will then apply when changing runlevel from S to
+whatever the next runlevel is set to be (default 2).  E.g., generate a
+`/etc/chrony.conf` and call `initctl enable chronyd`.
+
+**Options:**
+
+ - `progress`: display the progress of each script being executed
+ - `sysv`: run only SysV style scripts, i.e., `SNNfoo`, or `KNNbar`,
+   where `NN` is a number (0-99).
+
+If global debug mode is enabled, the `runparts` program is also called
+with the debug flag.
+
+**Limitations:**
+
+Scripts called from `runparts`, or hook scripts (see below), are limited
+in their interaction with Finit.  Like the standalone `run` stanza and
+the `/etc/rc.local` shell script, Finit waits for their completion
+before continuing.  None of them can issue commands to start, stop, or
+restart other services.  Also, ensure all your services and programs
+either terminate or start in the background or you will block Finit.
+
+> [!NOTE]
+> `runparts` scripts are only read and executed in runlevel S.  See
+> [hook scripts](../plugins.md#hooks) for other ways to run scripts at
+> certain points during the complete lifetime of the system.
+
+**Recommendations:**
+
+It can be beneficial to use `01-name`, `02-othername`, etc., to ensure
+the scripts are started in that order, e.g., if there is a dependency
+order between scripts.  Symlinks to existing daemons can talso be used,
+but make sure they daemonize (background) themselves properly, otherwise
+Finit will lock up.
+
+If `S[0-9]foo` and `K[0-9]bar` style naming is used, the executable will
+be called with an extra argument, `start` and `stop`, respectively.
+E.g., `S01foo` will be called as `S01foo start`.  Of course, `S01foo`
+and `K01foo` may be a symlink to to `another/directory/foo`.
+
+[run-parts(8)]: http://manpages.debian.org/cgi-bin/man.cgi?query=run-parts