update readme

Author: reugn

README.md

@@ -6,19 +6,18 @@
   <a href="https://codecov.io/gh/reugn/async"><img src="https://codecov.io/gh/reugn/async/branch/master/graph/badge.svg"></a>
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-Async provides synchronization and asynchronous computation utilities for Go.
-
-The implemented patterns were taken from Scala and Java.
+Async is a synchronization and asynchronous computation package for Go.
 
 ## Overview
 * **Future** - A placeholder object for a value that may not yet exist.
 * **Promise** - While futures are defined as a type of read-only placeholder object created for a result which doesn’t yet exist, a promise can be thought of as a writable, single-assignment container, which completes a future.
 * **Task** - A data type for controlling possibly lazy and asynchronous computations.
+* **WaitGroupContext** - A WaitGroup with the `context.Context` support for graceful unblocking.
 * **Reentrant Lock** - Mutex that allows goroutines to enter into the lock on a resource more than once.
 * **Optimistic Lock** - Mutex that allows optimistic reading. Could be retried or switched to RLock in case of failure. Significantly improves performance in case of frequent reads and short writes. See [benchmarks](./benchmarks/README.md).
 
 ## Examples
 Can be found in the examples directory/tests.
 
 ## License
-Licensed under the MIT License.
+Licensed under the MIT License.