Add an xC relay protocol analyzer

xR/xR.adoc

@@ -0,0 +1,41 @@
+xR(1)
+=====
+:doctype: manpage
+:manmanual: xK Manual
+:mansource: xK {release-version}
+
+Name
+----
+xR - xC relay protocol analyzer
+
+Synopsis
+--------
+*xR* [_OPTION_]... RELAY-ADDRESS...
+
+Description
+-----------
+*xR* connects to an *xC* relay and prints all incoming events one per line
+in JSON format.  The JSON objects have two additional fields:
+
+when::
+	The time of reception (or sending) as a nanosecond precision
+	RFC 3339 UTC timestamp.
+raw::
+	The incoming event (or outgoing command) in raw binary form.
+
+Options
+-------
+*-debug*::
+	Print any outgoing commands as well, which may help in debugging any issues.
+
+*-version*::
+	Output version information and exit.
+
+Reporting bugs
+--------------
+Use https://git.janouch.name/p/xK to report bugs, request features,
+or submit pull requests.
+
+See also
+--------
+*xC*(1)