Move default fonts to new crate epaint_default_fonts (#4853)

This allows license checking tools to omit the OFL and UFL licenses when
`default_fonts` are turned off.

There was some discussion of versioning on the original issue; I have
chosen to label this version as `0.28.1` to match the other crates.
Happy to adjust the version as needed.

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* Closes <https://github.com/emilk/egui/issues/2321>
* [X] I have followed the instructions in the PR template

---------

Co-authored-by: Alex Pinkus <pinkus@amazon.com>

crates/epaint_default_fonts/Cargo.toml

@@ -0,0 +1,29 @@
+[package]
+name = "epaint_default_fonts"
+version.workspace = true
+authors = ["Emil Ernerfeldt <emil.ernerfeldt@gmail.com>"]
+description = "Default fonts for use in epaint / egui"
+edition.workspace = true
+rust-version.workspace = true
+homepage = "https://github.com/emilk/egui/tree/master/crates/epaint_default_fonts"
+license = "(MIT OR Apache-2.0) AND OFL-1.1 AND LicenseRef-UFL-1.0" # OFL and UFL are from the font files themselves.
+readme = "README.md"
+repository = "https://github.com/emilk/egui/tree/master/crates/epaint_default_fonts"
+categories = ["graphics", "gui"]
+keywords = ["graphics", "gui", "egui"]
+include = [
+  "../LICENSE-APACHE",
+  "../LICENSE-MIT",
+  "**/*.rs",
+  "Cargo.toml",
+  "fonts/*.ttf",
+  "fonts/*.txt",
+  "fonts/OFL.txt",
+  "fonts/UFL.txt",
+]
+
+[lints]
+workspace = true
+
+[package.metadata.docs.rs]
+all-features = true