radicle-git init

Port over all git relevant parts of the radicle-link repository[0].
The packages that are kept are:
* git-ext
* git-ref-format
* git-trailers
* link-git
* macros
* std-ext
* test -- only the portions that test the above

The development and testing scripts are also added for local and CI
testing.

[0]: https://github.com/radicle-dev/radicle-link/
Signed-off-by: Fintan Halpenny <fintan.halpenny@gmail.com>

link-git/src/protocol.rs

@@ -0,0 +1,30 @@
+// Copyright © 2021 The Radicle Link Contributors
+//
+// This file is part of radicle-link, distributed under the GPLv3 with Radicle
+// Linking Exception. For full terms see the included LICENSE file.
+
+use bstr::ByteSlice as _;
+use git_protocol::transport::client;
+use versions::Version;
+
+pub mod fetch;
+pub mod ls;
+pub mod packwriter;
+pub mod take;
+pub mod transport;
+pub mod upload_pack;
+
+pub use fetch::{fetch, Ref};
+pub use ls::ls_refs;
+pub use packwriter::PackWriter;
+pub use upload_pack::upload_pack;
+
+pub use git_hash::{oid, ObjectId};
+
+fn remote_git_version(caps: &client::Capabilities) -> Option<Version> {
+    let agent = caps.capability("agent").and_then(|cap| {
+        cap.value()
+            .and_then(|bs| bs.to_str().map(|s| s.to_owned()).ok())
+    })?;
+    Version::new(agent.strip_prefix("git/")?)
+}