OpenColorIO: Improve/Cleanup Implementation

This split the shader cache into caches for Shader, Lut and CurveMapping.

This way we can have smoother updates when tweaking/animating the color
managment (i.e. exposure and gamma should only recompile the shader).

The curvemapping, predivide and dither options are no longer compile time
optimized but use uniforms. I did not measure any performance difference.

DRW: Use Batch API instead of IMM for color managment

A little cleanup that should avoid some state changes and pipeline stall.

Cleanup: OpenColorIO: Remove state tracking

Theses are useless. Better assume the state is has been changed.

GPUViewport: Cleanup and use always use RGBA16F

GPU: Add sRGB framebuffer support

Only enable GL_FRAMEBUFFER_SRGB on framebuffer objects as the main
framebuffer is likely to be srgb, and as of now we don't use linear
color for area texture.

Cleanup: EEVEE: Move debug draw to eevee_renderpass.c

DRW: Move Color-Management handling to draw manager

This is first part of the color managmeent refactor.

The drawing of the overlays is done in a sRGB texture to retain some bits
of accuracy.

The transform is applied after the overlays blending for now.

There is much left to be done.

Cleanup: EEVEE: Remove alpha checker drawing

This will be ported to the overlay engine.

Overlay: Improve Outline diagonal Antialiasing

I doubt we can do much better. Most of the aliasing comes from the edge
detection which does not use a lot of samples. We could use more samples
but then the detection becomes way more complex and expensive.

The second issue comes from the reconstruction (AA pass) that only bleed
adjacent pixels in if their line direction is perpendicular to the offset.
This makes corner gaps on certain diagonals.

Fix T73187 Overlay: Stereo 3D Camera not displaying correctly