Mention use of git dependencies in README

lib/grammers-client/README.md

@@ -5,3 +5,12 @@ This library is a higher-level interface to interact with Telegram's API.
 It contains the code necessary to create a client, connect to the API and
 make Remote Procedure Calls (RPC) to it, such as signing in or sending a
 message.
+
+The library is in development, but new releases are only cut rarely.
+[Specifying the dependency from the git repository][dep-git] is recommended:
+
+```toml
+grammers-client = { git = "https://github.com/Lonami/grammers" }
+```
+
+[dep-git]: https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#specifying-dependencies-from-git-repositories