add description for v4

README.md

@@ -11,15 +11,26 @@
 [![Research][icon_research]][page_research]
 [![License][icon_license]](LICENSE)
 
-## Differences from [Rican7/retry](https://github.com/Rican7/retry)
-
-- Fixed [bug](https://github.com/Rican7/retry/pull/2) with an unexpected infinite loop.
-  - Added a clear mechanism for this purpose as the Infinite [strategy](strategy/strategy.go#L24-L28).
-- Added support of cancellation (based on simple channel, e.g. `context.Done`).
-  - Made honest Action execution.
-- Added `error` transmission between attempts.
-  - Added `classifier` to handle them (see [classifier](classifier) package).
-- Added CLI tool `retry` which provides functionality for repeating terminal commands (see [cmd/retry](cmd/retry)).
+## Important news
+
+The **master** is a feature frozen branch for versions _3.3.x_ and no longer maintained.
+
+```bash
+$ dep ensure -add github.com/kamilsk/[email protected]
+```
+
+The **[v3][]** branch is a continuation of the **master** branch for versions _v3.4.y_
+to better integration with [Go Modules][gomod].
+
+```bash
+$ go get -u github.com/kamilsk/retry/[email protected]
+```
+
+The **[v4][]** branch is an actual development branch with many [features][v4_features].
+
+```bash
+$ go get -u github.com/kamilsk/retry/v4
+```
 
 ## Usage