* Refactor text layout: don't need &Fonts in all functions
* Replace indexing in Fonts with member function
* Wrap Fonts in a Mutex
* Remove mutex for Font::glyph_info_cache
* Remove RwLock around Font::characters
* Put FontsImpl and GalleyCache behind the same Mutex
* Round font sizes to whole pixels before deduplicating them
* Make TextStyle !Copy
* Implement user-named TextStyle:s
* round font size earlier
* Cache fonts based on family and size
* Move TextStyle into egui and Style
* Remove body_text_style
* Query graphics about max texture size and use that as font atlas size
* Recreate texture atlas when it is getting full
* Move texture allocation into epaint/egui proper
* Add TextureHandle
* egui_glow: cast using bytemuck instead of unsafe code
* Optimize glium painter
* Optimize WebGL
* Add example of loading an image from file
* add texture registering function
* fmt
* Revert "add texture registering function"
This reverts commit f9b4db12
* make get_texture public to get render target owned by Painter .
* revert egui_web painter.rs change
* Added shaders on GLSL 1.2
- Used `glium::program` to create shaders
- Moved shaders code to its own sources and include it as str
- Added shaders implementation on GLSL which allows run egui on old hardware
(Raspberry Pi 1/zero in game again)
* Moved webgl shaders code to sources in `shader` subdir
* Added GLSL ES shaders to glium backend to support OpenGL ES
* Described changes related to GLSL versions support
