Rename `ShaderImpl` to `Shader`
Remove TextureImpl
Remove ProgramImpl
Fix some warnings
Made `Display` clonable
Add libosmesa6-dev for travis
No longer call `get_inner_size` at each frame
No longer use Arcs for Shaders
Remove deprecated functions from Display
Fix example not up-to-date
Hide vertex_buffer::get_clone function
Fix typo in vertex buffer doc
Add better doc for `uniforms` module
Split `Texture` into multiple structs
Change input data format for textures
Remove title from `uniforms` module docs
Update token for rust-ci docs
Better doc for texture module
Add draw to Texture2D
Add backface_culling to DrawParameters