Updating zlib to 1.2.8 so the CMake download works again.
Normalizing the location the files request SDL headers from.
Fixing the CMake project for SDL on Windows to put the SDL headers in a SDL sub-folder.
Modifying the SDL CMake project to put dlls in the same bin location.

Added instructions to the README.md to explain how to run the application on Windows.
Merge pull request #124 from kiyote/master

Build process updates, including zlib-1.2.8 and better SDL support on Windows.