message: Update changelog, or attempt to.
diff: * Added line cap and join options
  * Added spatial sources for audio
  * Added `From` implementations for `Color` to convert from various tuples of `f32`'s. Redundant but it annoyed me they don't exist.
  + * Add OpenGL ES 3.0 support
  + * Add optional textures to `Mesh`es.
  + * Added lots of tests and doctests.
  ## Changed
  * What used to be the `TextCached` module is now the `Text` module, replacing all the old text stuff. This *dramatically* changes the text API, as well as being faster and more powerful.
  * Various dimension parameters have changed to fit the underlying implementations more closely. `Image` dimensions have changed from `u32` to `u16`, which they always were but now it's exposed to the API. Various screen size dimensions have changed from `u32` to `f64`, which allows `winit` to do smooth DPI-independent scaling.
  * Various getters have been renamed from `get_<field>()` to `<field>`(). Of particular note are changes to Drawable and ShaderHandle traits.
  + * Probably tons of other things I've forgotten.
  + * We now target Rust 2018
  + * Some minor modularization has taken place; at least, gamepad and audio module scan be disabled with settings in your `conf.toml`. Doing the same for filesystem, graphics, and input is a liiiiiittle more involved.
  + *
  ## Deprecated
  