Remove the UnityConsole unity package

Three unity packages are instead be available separately for download
from the UnityConsole website at http://wenzil.github.io/UnityConsole/
- UnityConsoleMinimal which does not include example scenes and assets
- UnityConsoleWithExampleScenes which includes useful step-by-step
learning examples
- UnityConsoleVRDemoAlpha which includes a basic demo for early stage VR
support

Example scenes have also been updated and some project and scene clutter
has been removed
Improve encapsulation and more XML comments

Fields intended to be exposed to the inspector in ConsoleUI and
ConsoleController were public. Instead, they are now private and have
the [SerializeField] attribute applied to them. This results in better
encapsulation.

Public members with missing XML comments have been taken care of.