publish client-sdk-native (#12)

* Create README.md

* add example

* crates & examples

* fix syntax

* add LICENSE

* thirdparty LICENSE

* rearrange repo

* fix build

* egui versions

* prepare publish

* fix demo compilation

* add test ci

* Update rust.yml

* forgot runs-on

* install protoc before building

* avoid rate limit

* include submodules

* updates to readme

* cache rust builds

Co-authored-by: David Zhao <dz@livekit.io>
Co-authored-by: David Zhao <david@davidzhao.com>

.gitmodules

@@ -1,3 +1,3 @@
-[submodule "crates/livekit-core/protocol"]
-	path = crates/livekit-core/protocol
+[submodule "livekit/protocol"]
+	path = livekit/protocol
 	url = https://github.com/livekit/protocol