Update README.md (#1600)

Fixed artifact name to `async-http-client-extras-typesafe-config`, there was a missing dash

Author: gsilvestrin

extras/typesafeconfig/README.md

@@ -8,20 +8,20 @@ Download [the latest JAR][2] or grab via [Maven][3]:
 ```xml
 <dependency>
   <groupId>org.asynchttpclient</groupId>
-  <artifactId>async-http-client-extras-typesafeconfig</artifactId>
+  <artifactId>async-http-client-extras-typesafe-config</artifactId>
   <version>latest.version</version>
 </dependency>
 ```
 
 or [Gradle][3]:
 
 ```groovy
-compile "org.asynchttpclient:async-http-client-extras-typesafeconfig:latest.version"
+compile "org.asynchttpclient:async-http-client-extras-typesafe-config:latest.version"
 ```
 
  [1]: https://github.com/lightbend/config
- [2]: https://search.maven.org/remote_content?g=org.asynchttpclient&a=async-http-client-extras-typesafeconfig&v=LATEST
- [3]: http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22org.asynchttpclient%22%20a%3A%22async-http-client-extras-typesafeconfig%22
+ [2]: https://search.maven.org/remote_content?g=org.asynchttpclient&a=async-http-client-extras-typesafe-config&v=LATEST
+ [3]: http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22org.asynchttpclient%22%20a%3A%22async-http-client-extras-typesafe-config%22
  [snap]: https://oss.sonatype.org/content/repositories/snapshots/
 
 ## Example usage
@@ -31,4 +31,4 @@ compile "org.asynchttpclient:async-http-client-extras-typesafeconfig:latest.vers
 com.typesafe.config.Config config = ...
 AsyncHttpClientTypesafeConfig ahcConfig = new AsyncHttpClientTypesafeConfig(config);
 AsyncHttpClient client = new DefaultAsyncHttpClient(ahcConfig);
-```
+```