OpenFace 2.0.3

A lot of house-keeping: updating libraries and extra testing on various Ubuntu versions.

Changelog:

• Big re-org and cleanup of CMake (thanks aleh-arol - https://github.com/aleh-arol and severin-lemaignan - https://github.com/severin-lemaignan)
• CMake is now only for Ubuntu and OSX, while for windows builds use Visual Studio 2015
• Updating dlib to 19.13
  • Bringing up to recent build that has fewer clashes with OpenBLAS and boost
  • Now the code will require a separate build to link to on OS X and Ubuntu (this will allow users to re-use their own dlib builds and will increase stability)
• Instructions and testing for Ubuntu 14, 16, and 18
• Fixing boost and dlib clashes, that resulted in requiring a certain version of boost, now most versions of boost should work
• OpenBLAS include fixes with testing on Ubuntu 14.04, 16.04, 18.04, and OS X
• Some of the issues were caused by Ubuntu 14.04 openblas install not containing headers
• Some CNN util cleanup
• Cleaning up includes in Cpp interop code
• Bug fixes:
  • Really short executables using FeatureExtraction
• Option to process .webm files in the GUI