Adapt markdown Content table

Author: frederic34

readme.md

@@ -10,10 +10,10 @@ Firmata is a protocol for communicating with microcontrollers from software on a
 - [Firmata Client Libraries](#firmata-client-libraries)
 - [Updating Firmata in the Arduino IDE - Arduino 1.6.4 and higher](#updating-firmata-in-the-arduino-ide---arduino-164-and-higher)
 - [Cloning Firmata](#cloning-firmata)
-- [Updating Firmata in the Arduino IDE - older versions (<= 1.6.3 or 1.0.x)](#updating-firmata-in-the-arduino-ide---older-versions---163-or-10x)
-        - [Mac OSX:](#mac-osx)
-        - [Windows](#windows)
-        - [Linux](#linux)
+- [Updating Firmata in the Arduino IDE - older versions (<= 1.6.3 or 1.0.x)](#updating-firmata-in-the-arduino-ide---older-versions--163-or-10x)
+  - [Mac OSX:](#mac-osx)
+  - [Windows](#windows)
+  - [Linux](#linux)
 - [Using the Source code rather than release archive (only for versions older than Arduino 1.6.3)](#using-the-source-code-rather-than-release-archive-only-for-versions-older-than-arduino-163)
 - [Contributing](#contributing)