Refactor: move things into eframe (#1542)

* Move all epi-related code from egui_glow into eframe

* Move epi stuff from egui-winit into eframe

* Remove mention of epi in egui

* Remove mention of epi in egui_glium

* Remove trait epi::NativeTexture

* Remove confusing mentions of epi

* Refactor egui_web: break up into smaller files

* Clean up feature flags further, and update changelogs

* Clean up check.sh

* Small cleanup of egui_web/Cargo.toml

* Fix dependencies for pure_glow example

* Fix clippy false positive

Cargo.lock

@@ -1075,11 +1075,16 @@ checksum = "6907e25393cdcc1f4f3f513d9aac1e840eb1cc341a0fccb01171f7d14d10b946"
 name = "eframe"
 version = "0.17.0"
 dependencies = [
+ "dark-light",
  "egui",
  "egui-winit",
  "egui_glow",
  "egui_web",
  "epi",
+ "glow",
+ "glutin",
+ "puffin",
+ "winit",
 ]
 
 [[package]]
@@ -1099,10 +1104,7 @@ name = "egui-winit"
 version = "0.17.0"
 dependencies = [
  "arboard",
- "dark-light",
  "egui",
- "epi",
- "glow",
  "instant",
  "puffin",
  "serde",
@@ -1178,7 +1180,6 @@ dependencies = [
  "bytemuck",
  "egui",
  "egui-winit",
- "epi",
  "glow",
  "glutin",
  "memoffset",