docs: Update README & INSTALL files.

  * Add INSTALL.markdown
  * Update README.markdown.
    - Add link to Neuromancer, the book.
  * Add more documentation tools and content.
    - Add Code of Conduct for the Wintermute project.
    - Introduce Doxygen generation of docs.
    - Add CMake updates to handle Doxygen and Graphviz.
    - Add Doxygen template file.
    - Made the base Doxygen configuration a bit tighter.
    - Update Doxygen configuration.
    - Add layout for documentation site.
    - Update documentation config and CMake.
    - Updat ignores, Doxygen templates and doc generation.
    - Update document generation for Wintermute.
    - Fix issue with mainpage being included.
    - Allow extra files to be loaded in for README purposes.
    - Add version file, move docs into silo.
vagrant: Add support for Vagrant.

  * Support for Vagrant has been added.
  * Ensure that latest packages are used.
cmake: Bumped minimum version of CMake to 2.8.12.