Make the manpages mostly acceptable

Closes #1

README.adoc

@@ -50,8 +50,12 @@ Or you can try telling CMake to make a package for you.  For Debian it is:
 There is also a Makefile you can use to quickly build a binary to be copied
 into the PATH of any machine you want to have 'sdn' on.
 
+Configuration
+-------------
+For a slightly more technical explanation please refer to manual pages.
+
 Integration
------------
+~~~~~~~~~~~
 The package contains an installation script called 'sdn-install' which will bind
 'sdn' to Alt-o in your shell's initialisation file.  The supported shells are:
 
@@ -64,9 +68,6 @@ elvish is absolutely perverse.  And so is integrating 'sdn' into it because it
 already includes a custom file manager, bound to Ctrl-N (though I find the
 ranger-like interface confusing and resource-demanding).
 
-Configuration
--------------
-
 Colours
 ~~~~~~~
 Here is an example of a '~/.config/sdn/look' file; the format is similar to
@@ -91,7 +92,6 @@ To obtain more vifm-like controls, you may write the following to your
 ....
 normal h parent
 normal l choose
-normal ? help
 ....
 
 Helper programs

sdn-install.1

@@ -1,4 +1,4 @@
-.Dd October 26, 2020
+.Dd October 27, 2020
 .Dt SDN-INSTALL 1
 .Os Linux
 .Sh NAME
@@ -22,9 +22,14 @@ Merely print the integration snippet for the appropriate shell to the standard
 output, not changing anything.
 .It Fl p Ar rcpath
 Install the integration snippet into a different shell initialization file than
-your user's default one.
+the default one for your user.
 .It Fl s Ar shell
 If you want to integrate
 .Xr sdn 1
-with a different shell than you're running, use this option to specify it.
+with a different shell than the one you're running, use this option to specify
+it.
 .El
+.Sh REPORTING BUGS
+Use
+.Lk https://git.janouch.name/p/sdn
+to report bugs, request features, or submit pull requests.

sdn.1

@@ -1,18 +1,59 @@
-.Dd October 26, 2020
+.Dd October 27, 2020
 .Dt SDN 1
 .Os Linux
 .Sh NAME
 .Nm sdn
-.Nd simple directory navigator
+.Nd directory navigator
 .Sh SYNOPSIS
 .Nm sdn
 .Op Ar line Ar point
+.Nm sdn
+.Cm --version
 .Sh DESCRIPTION
 .Nm
-is a simple directory navigator that you can invoke while editing shell
+is a simple directory navigator that you can launch while editing shell
 commands.  Use the
 .Xr sdn-install 1
-script to integrate it with your shell, then invoke it with M-o.
+script to integrate it with your shell, then invoke it at any time with M-o.
+.Pp
+Press F1 to get a list of active key bindings and their assigned actions,
+grouped by their contexts.
+.Pp
+Program arguments are only used by integration snippets to forward the parent
+shell's command line.  The
+.Ar point
+is given in terms of characters.
+.Sh OPTIONS
+While some behaviour can be toggled from within the program, some can only be
+changed by modifying configuration files manually.
+.Pp
+The files follow a simple syntax derived from the Bourne shell: each option is
+on its own line, with words separated by linear whitespace.  Comments start with
+a hash (#) and continue until the end of the line.  All special characters may
+be quoted using either a backslash or single-quoted strings.
+.Pp
+The options and the default key bindings controlling them are as follows:
+.Bl -tag
+.It full-view Em bool No (t)
+If non-zero, the equivalent format to
+.Ql ls -l
+is used to display directory contents rather than simply listing the filenames.
+.It gravity Em bool
+If non-zero, all entries stick to the bottom of the screen, i.e., all empty
+space is at the top.
+.It reverse-sort Em bool No (R)
+If non-zero, the order of entries is reversed.
+.It show-hidden Em bool No (M-.)
+If non-zero, filenames beginning with a full stop are shown.
+.It ext-helpers Em bool
+If non-zero, viewers and editors are launched from the parent shell.  This way
+you can suspend them and use job control features of the shell.  However it
+also enforces any pending change to the shell's working directory.
+.It sort-column Em number No (M-< M->)
+The zero-based index of the
+.Ql full-view
+column that entries are ordered by.
+.El
 .Sh ENVIRONMENT
 .Bl -tag -width 15n
 .It Ev LS_COLORS
@@ -23,16 +64,45 @@ and you can use the
 utility to initialize this variable.
 .It Ev PAGER
 The viewer program to be launched by the F3 key binding as well as to show
-the internal help message.
+the internal help message.  If none is set, it defaults to
+.Xr less 1 .
 .It Ev VISUAL , Ev EDITOR
-The editor program to be launched by the F4 key binding.
+The editor program to be launched by the F4 key binding.  If none is set,
+it defaults to
+.Xr vi 1 .
 .El
 .Sh FILES
 .Bl -tag -width 25n -compact
 .It Pa ~/.config/sdn/config
-Program configuration and state.
+Program configuration and navigation state, initialized or overwritten on exit.
 .It Pa ~/.config/sdn/bindings
-Key binding overrides.
+Custom key binding overrides.
 .It Pa ~/.config/sdn/look
 Redefine terminal attributes for UI elements.
 .El
+.Sh EXAMPLES
+.Ss Pa bindings
+Key names or combinations follow the Emacs syntax for Control and Meta prefixes
+and
+.Xr terminfo 5 names are used for special keys.  To obtain more vifm-like
+controls and Windows-like quit abilities:
+.Bd -literal -offset indent
+normal h parent
+normal l choose
+normal M-f4 quit
+.Ed
+.Ss Pa look
+Terminal attributes are accepted in a format similar to that of
+.Xr git 1 , only named colours aren't supported.  For a black-on-white terminal
+supporting 256 colours, a theme such as the following may work:
+.Bd -literal -offset indent
+cursor 231 202
+bar 16 255 ul
+cwd bold
+input
+cmdline 145
+.Ed
+.Sh REPORTING BUGS
+Use
+.Lk https://git.janouch.name/p/sdn
+to report bugs, request features, or submit pull requests.