Update README for swift-etcd-client (#12)

Update README to add getting started, overview, and contributing
information.

---------

Co-authored-by: “Ayushi <“[email protected]”>

Author: ayushi2103

README.md

@@ -1,13 +1,79 @@
 # 🚧WIP🚧: Swift ETCD client
 
-ETCD is a Swift Package in development that provides a convenient way to communicate with [etcd](https://etcd.io) servers.
+Swift ETCD is a Swift Package that provides a convenient way to communicate with [etcd](https://etcd.io) servers.
 
 ## Getting Started
+To depend on Swift ETCD within your own project, you can add a `dependencies` clause to your `Package.swift`
+```
+dependencies: [
+    .package(url: "https://github.com/swift-server/swift-etcd-client-gsoc")
+]
+```
 
 ## Overview
+The ETCD Client allows for communication with an ETCD Server. The Client takes care of establishing a connection, and handling asynchronous execution of commands.
 
-TBD
+Here's an example of how you can use the ETCD Client
 
-## Contributing
+```swift
+struct Example {
+    static func main() async throws {
+        let eventLoopGroup = MultiThreadedEventLoopGroup.singleton
+        do {
+            let etcdClient = EtcdClient(host: "localhost", port: 2379, eventLoopGroup: eventLoopGroup)
+            try await withThrowingTaskGroup(of: Void.self) { group in
+                group.addTask {
+                    do {
+                        try await etcdClient.watch("foo") { sequence in
+                            var iterator = sequence.makeAsyncIterator()
+                            while let event = try await iterator.next() {
+                                print(event)
+                            }
+                        }
+                    } catch {
+                        print("Error watching key: \(error)")
+                    }
+                }
+                // Sleeping for a second to let the watch above setup
+                try await Task.sleep(for: .seconds(1))
+                
+                try await etcdClient.set("foo", value: "bar")
+                let key = "foo".data(using: .utf8)!
+                let rangeRequest = RangeRequest(key: key)
+                if let value = try await etcdClient.getRange(rangeRequest) {
+                    if let stringValue = String(data: value, encoding: .utf8) {
+                        print("Value is: \(stringValue)")
+                        let deleteRangeRequest = DeleteRangeRequest(key: key)
+                        try await etcdClient.deleteRange(deleteRangeRequest)
+                        print("Key deleted")
+                        
+                        // Trying to get the value again
+                        let deletedValue = try await etcdClient.getRange(rangeRequest)
+                        if deletedValue == nil {
+                            print("Key not found after deletion")
+                        } else {
+                            print("Value after deletion: \(deletedValue!)")
+                        }
+                    } else {
+                        print("Unable to get value")
+                    }
+                } else {
+                    print("Key not found")
+                }
+                try await Task.sleep(for: .seconds(2))
+                do {
+                    try await etcdClient.set("foo", value: "updated_value")
+                } catch {
+                    print("Error setting updated value: \(error)")
+                }
+            }
+        } catch {
+            print("Error: \(error)")
+        }
+    }
+}
+
+```
 
-TBD
+## Contributing
+To contribute to this package, please look at [CONTRIBUTING.md](./CONTRIBUTING.md)