[gnome-battery-bench] docs: document the 'gbb info' command

[Christian Kellner <gicmo src gnome org>]

commit d29a408d7b6fee54b78972bfbe8394e0dbe6e187
Author: Christian Kellner <gicmo gnome org>
Date:   Mon May 8 18:38:20 2017 +0200

    docs: document the 'gbb info' command

 docs/gbb.txt |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)
---
diff --git a/docs/gbb.txt b/docs/gbb.txt
index 196601f..336d441 100644
--- a/docs/gbb.txt
+++ b/docs/gbb.txt
@@ -8,6 +8,7 @@ gbb - Command line integration client for GNOME Battery Bench
 SYNOPSIS
 --------
 [verse]
+'gbb info [--json]'
 'gbb monitor'
 'gbb play <filename>'
 'gbb play-local <filename>'
@@ -29,6 +30,17 @@ http://git.gnome.org/browse/gnome-battery-bench/plain/README[README file]
 COMMANDS
 --------
 
+info
+~~~~
+
+'gbb info'
+
+Display general hardware and software information. The information is not exhaustive,
+focuses on power relevant components and is meant as a means to identify different
+platforms and systems. If '--json' is specified then the output will be in the machine
+readable JSON format; here unknown components will be omitted instead of reported as
+"Unknown".
+
 monitor
 ~~~~~~~