Added a new texture for testing with

|CONTENT|
[Texture/Biohazard]
* A black biohazard symbol on a red background
Changed the depth test to less or equal, which fixed the rendering issue

|SOURCE|
[Common/Renderer]
* Changed the depth function to use less or equal instead of greater or equal
* All three G-buffers are rendered to display the contents
* Instances of glBindFrameBuffer where the framebuffer should be both read from
  and written to use the GL_FRAMEBUFFER enum
* Set the framebuffer width and height (haven't tested if this changes
  anything)
* Clear colour for the G-buffers is set to black
[Common/Texture]
* Added LoadFromFile which was incorrectly lost in the last merge

|CONTENT|
[Shaders/TexturedSimple]
* Added layout( location ) to each output pixel
* WorldPosition uses the world position calculated in the vertex shader
* Albedo is sampling the texture instead of outputting a solid colour