Update README.md (JabRef#4419)

* Update README.md

Remove obsolete integration test description. Add a note on travis

* Fix travis link

* Update README.md

Missing comma

README.md

@@ -101,7 +101,7 @@ When you want to develop, it is necessary to generate additional sources using `
 and then generate the Eclipse `gradlew eclipse`.
 For IntelliJ IDEA, just import the project via a Gradle Import by pointing at the `build.gradle`.
 
-`gradlew test` executes all tests. We use Travis CI[https://travis-ci.org/] for executing the tests after each commit. For developing it is sufficient to locally only run the associated test for the classes you changed. Travis will report any other failure.
+`gradlew test` executes all tests. We use [Travis CI](https://travis-ci.org/) for executing the tests after each commit. For developing, it is sufficient to locally only run the associated test for the classes you changed. Travis will report any other failure.
 
 
 ## Acknowledgements