make install enabled

The shared library, headers and a cmake file can be make installed
Definitions and headers for threads added
Added include <algorithm>
Added type in std::min/std::max
Added include <math.h> and _USE_MATH_DEFINES if WIN32
Added Ubuntu documentation
Formatting README to Markdown format
Merge pull request #77 from davetcoleman/upmaster_readme_formatting

Formatting README to Markdown format. Thanks @davetcoleman!
Merge pull request #67 from larshg/libfreenect2mathfix

Added include <algorithm> in ifdef WIN32 and VS2013
replaced libusb_get_port_number with libusb_get_device_address to correctly identify devices, fixes #65
Merge pull request #80 from christiankerl/fix_device_identification

fix device identification
Made a ifdef for packing data to work on windows also.
Path of freenect2Config.cmake fixed
Merge pull request #52 from dorian3d/feature/install

make install enabled
Merge pull request #66 from larshg/libfreenect2packeddata

Made a ifdef for packing data to work on windows also.
added opencl implementation of the depth processor.
cleaned up CMakeLists.txt. Removed c++11 dependency.
Parameters are now read in from the Parameters struct.
Config is read from the Config struct.
Removed unused variables from opencl code.
using found opencl library.
Get the missing cl.hpp from Khronos.org
Allow apple platforms to find the cl.hpp file
fixing compilation if opencl is not available