Remove egui_web and epi (#1545)

* Remove integration name (it is always eframe)

* Remove egui_web crate

* Move egui_web/CHANGELOG.md into eframe/CHANGELOG.md

* Remove all mentions of egui_web

* Remove epi crate and absorb into eframe

* egui_glow: only use puffin on native

* Remove WASM doc from CI (we don't generate it anyways!)

* Remove eframe::epi and improve eframe docs

egui-winit/src/lib.rs

@@ -451,7 +451,7 @@ impl State {
             open_url,
             copied_text,
             events: _,                    // handled above
-            mutable_text_under_cursor: _, // only used in egui_web
+            mutable_text_under_cursor: _, // only used in eframe web
             text_cursor_pos,
         } = platform_output;