Examples have been reworked to better align with the intended usage
scenarios for Igneous: the implementation of custom Renderer systems
that provide high-level data management and pipeline execution models
beyond the low-level details of pipeline-specific processes.

Rather than deriving from GraphicsPipeline, each example now derives
from MainWindow, which serves as a simplified Renderer aggregating a
WindowSurface, VBO/IBO data, and generic kPipeline instances. Each
example, in its constructor, creates its own set of pipelines and data
sources.

Maintenance

Obsolete routines and data have been removed from the pipeline class
hierarchy, due to VBO and IBO being externalized.

Closes #4

IGN-gen-docs