Merge pull request #63 from Kimundi/master

Updated gl-rs submodule
Remove one layer of indirection when rendering
Remove obsolete comments
Merge pull request #64 from bjz/renderer-refactor

Remove one layer of indirection when rendering
Added device target module. Implemented plane binding.
Implemented FBO creation and frame management on the render side.
Implemented depth/stencil clears
Merged with new render module
Merge pull request #65 from kvark/frame

Framebuffer support
Use a future to allow the Renderer to be lazily initialised once the device can process requests
Merge pull request #66 from bjz/future

Use a future to allow the Renderer to be lazily initialised
Switch from DuplexStream to raw Senders and Receivers

`DuplexStream` is now deprecated.

Closes #67.
Merge pull request #68 from bjz/dewarningify

Switch from DuplexStream to raw Senders and Receivers
swap_ack implemented with controllable queue size
Added Travis icon to README
Merge pull request #69 from kvark/ack

swap_ack implemented with controllable queue size
Make platform and render modules free-standing crates and make gfx a facade
Merge pull request #70 from bjz/facade

Make platform and render modules free-standing crates and make gfx a facade
Added initial support for different shader languages.

Instead of a `&[u8]` or `Vec<u8>`, shaders are now represented by a
`ShaderSource` type that can contain different shader source
languages. The device then selects the right one at runtime.
Merge pull request #72 from Kimundi/compat_gl_shader

Added initial support for different Shader languages.