doc: read version from Makefile

copyright = u'2015, Intel Corporation, Wind River Systems, Inc'

author = u'many'

# The version info for the project you're documenting, acts as replacement for

# |version| and |release|, also used in various other places throughout the

# built documents.

#

# The short X.Y version.

version = os.getenv('KERNELVERSION','0.1.0')

# The full version, including alpha/beta/rc tags.

release = os.getenv('KERNELVERSION','0.1.0')

# The following code tries to extract the information by reading the Makefile,

# when Sphinx is run directly (e.g. by Read the Docs).

try:

    makefile_version_major = None

    makefile_version_minor = None

    makefile_patchlevel = None

    for line in open('../Makefile'):

        key, val = [x.strip() for x in line.split('=', 2)]

        if key == 'VERSION_MAJOR':

            makefile_version_major = val

        if key == 'VERSION_MINOR':

            makefile_version_minor = val

        elif key == 'PATCHLEVEL':

            makefile_patchlevel = val

        if makefile_version_major and makefile_version_minor and makefile_patchlevel:

            break

except:

    pass

finally:

    if makefile_version_major and makefile_version_minor and makefile_patchlevel:

        version = release = makefile_version_major + '.' + makefile_version_minor + '.' + makefile_patchlevel

    else:

        sys.stderr.write('Warning: Could not extract kernel version\n')

        version = release = "unknown version"

        version = release = os.getenv('KERNELVERSION','0.1.0')

# The language for content autogenerated by Sphinx. Refer to documentation

# for a list of supported languages.

.. only:: (development or daily)

   Welcome to the Zephyr Project's documentation. This is the documentation of the

   master tree under development.

   master tree under development (version |version|).

   Documentation for released versions of Zephyr can be found at

   ``https://www.zephyrproject.org/doc/<version>``. The following documentation