message: Retroactively add changelog entries
  This adds versions 0.15 through 0.19 changelogs. I've created these
  from looking at git history, so they may not be entirely representitive
  of what's the most important change. They should mention everything,
  but may mis-prioritize.
diff: - Updated smallvec from version 0.4 to 0.6.
  - Updated misc internal dependencies and dev-dependencies (lazy_static, cgmath, rand, image, gl_generator).
  +## Version 0.19.0 (2017-12-11)
  +
  + - Updated glutin to version 0.11. Notably includes the [winit 0.9 update](https://github.com/tomaka/winit/blob/master/CHANGELOG.md#version-090-2017-12-01).
  + - Updated gl_generator to 0.7 (internal dependency).
  +
  +## Version 0.18.1 (2017-11-05)
  +
  + - Fixed links pointing to tomaka/glium instead of glium/glium
  + - Various documentation updates, bugfixes, and dependency updates.
  +
  +## Version 0.18.0 (2017-10-15)
  +
  + - Updated glutin to version 0.10.
  + - Added support for is_buffer_supported usage on all buffer types.
  + - Various documentation updates and bugfixes.
  +
  +## Version 0.17.1 (2017-08-27)
  +
  + - Changed documentation to docs.rs.
  + - Various bugfixes and updates to internal dependencies.
  +
  +## Version 0.17.0 (2017-07-12)
  +
  + - Updated glutin to version 0.9.
  + - Redesigned API around EventsLoop to match updated winit design.
  + - Added support for vector normalization.
  + - Various bugfixes.
  +
  +## Version 0.16.0 (2017-01-07)
  +
  + - Added asynchronous screenshot example.
  + - Updated tutorials to compile on Mac OS X.
  + - Various tutorial documentation updates.
  + - Fix buffer reads which could fail being safe.
  + - Various bugfixes.
  +
  +## Version 0.15.0 (2016-07-03)
  +
  + - Updated glutin to version 0.6.1
  + - Various internal dependency updates.
  +
  ## Version 0.14.0 (2016-04-11)
  - Updated glutin to version 0.5.
  