Examples for 'Finding the difference between two strings in Java' (#7625)

* initial commit

* Reformatting and addressing review comments

* Examples for 'Finding the difference between two strings in Java'

* Removing evaluation article code

* Adding benchmarks

* Removing performance tests from unit test class

* upgrading diff-match-patch version

* making benchmark methods return a value

* Moving code to java-strings-3

* Moving stuff around

* New unit test format

java-strings-3/pom.xml

@@ -68,6 +68,12 @@
             <version>${assertj.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.bitbucket.cowwoc</groupId>
+            <artifactId>diff-match-patch</artifactId>
+            <version>1.2</version>
+            <scope>test</scope>
+        </dependency>
 
         <!-- Added for password generation -->
         <dependency>