Continue towards creating unified build settings.

The goal of the addition of `Debug.props` and `Release.props` was to
move common settings away from individual projects, and instead move
them to a more reusable area. The result is a series of easily
maintainable settings that are used by all projects during different
builds.

The addition of `Common.props` however, goes a step further by storing
__all__ major settings (opposed to just differing build configurations)
in a single file.

`Common.props` presents the current settings at the time of its
creation:

 * Automatically import either `Debug.props` or `Release.props` based on
   the current build configuration,
 * State that two target platforms exist (`Win32` and `x64`) both with a
   debug and release configuration,
 * _Normalise_ build output and immediate directories across all
   configurations,
 * Add local `bin`, `include`, `lib`, and `src` directories to their
   respective paths,
 * Run static code analysis after a build completion,
 * Inform MSBuild to treat all warnings as errors, and
 * Include source code files in a more simplistic manner.

The side-effect of creating this file is that every buildable project
must now include this property file somewhere. However, this trade off,
against easily maintainable common properties, is relatively
insignificant.