Merge pull request #11 from zed-industries/undo

Introduce undo/redo support for arbitrary operations in `Buffer`

Cargo.lock

@@ -1692,6 +1692,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 
+[[package]]
+name = "seahash"
+version = "4.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1c107b6f4780854c8b126e228ea8869f4d7b71260f962fefb57b996b8959ba6b"
+
 [[package]]
 name = "semver"
 version = "0.9.0"
@@ -2270,6 +2276,7 @@ dependencies = [
  "parking_lot",
  "rand 0.8.3",
  "rust-embed",
+ "seahash",
  "serde_json",
  "simplelog",
  "smallvec",