Updated SDK download instructions. (Ported changes from DevSite.)

native_client_sdk/src/doc/sdk/index.rst

-.. _sdk-index:
-
-#################
-Native Client SDK
-#################
-
-To build Native Client modules, you must download and install the Native
-Client Software Development Kit (SDK).
-
-The SDK includes the following:
-
-support for multiple Pepper versions
-  The SDK contains **bundles** that let you compile Native Client modules
-  using different versions of the
-  `Pepper API </overview.html#link_pepper>`_
-  (e.g., Pepper 30 or Pepper Canary). Review the
-  :doc:`Release Notes <release-notes>` for a description of the new features
-  included in each Pepper version to help you decide which bundle to
-  use to develop your application. In general, Native Client modules
-  compiled using a particular Pepper version will work in
-  corresponding versions of Chrome and higher. For example, a module
-  compiled using the Pepper 30 platform will work in Chrome 30 and
-  higher.
-
-update utility
-  The ``naclsdk`` utility (``naclsdk.bat`` on Windows) lets you download new
-  bundles that are available, as well as new versions of existing bundles.
-
-toolchains
-  Each platform includes three toolchains---one for Portable Native Client
-  (PNaCl) applications, one for compiling architecture-specific Native
-  Client applications with newlib, and a third native NaCl toolchain for
-  compiling with glibc. Newlib and glibc are two different implementations
-  of the C standard library. All toolchains contain Native Client-compatible
-  versions of standard compilers, linkers, and other tools.
-  See :doc:`this document </nacl-and-pnacl>` to help you choose the
-  right toolchain.
-
-examples
-  Each example in the SDK includes C or C++ source files and header files
-  illustrating how to use NaCl and Pepper, along with a Makefile to build
-  the example using each of the toolchains.
-
-tools
-  The SDK includes a number of additional tools, which you can use for
-  tasks such as validating Native Client modules and running modules
-  from the command line.
-
-To download and install the SDK, follow the instructions on the
-:ref:`Download <download>` page.
-