Attempt to fix sphinx import errors

This fixes a problem with Sphinx producing documentation for the library

Adds partial documentation for Rust code

This release adds partial documentation and artificial type signatures (supported by Sphinx) for:

• window.events.Event
  • ...and all members
• window.events.RenderArgs
  • ...and all members
• window.events.UpdateArgs
  • ...and all members
• window.events.Viewport
  • ...and all members
• window.events.EventSettings
  • ...and all members
• window.events.Events
  • ...and all members
• opengl.draw

Full documentation

All functions and classes now provide documentation and Python signatures for Sphinx.

Other changes

• Context now has a view property (for view transformations)

Exposes transformations for context and drawing

As of this version, versioning will become stricter. Still assume that every commit is breaking until v1.0.0.

New features

• Exposes transformations (partially) and allows passing transformations to draw functions

Current features

• Exposed Window and WindowSettings API, using glutin_window::GlutinWindow in the backend
• Partial GlGraphics bindings, with control over draw events
• Event handling
  • Mouse and Keyboard events (and appropriate classes)
  • Events event loop manager with EventSettings
• graphics::rectangle and graphics::circle_arc exposed functions
• Python stub files mirroring Rust API