Add basic alogirthm, string reverse code

Author: jbee37142

src/test/java/algorithm/basic/StringReverse.java

@@ -3,8 +3,6 @@
 import org.junit.Test;
 import utils.Utils;
 
-import java.util.Stack;
-
 import static org.hamcrest.CoreMatchers.is;
 import static org.junit.Assert.assertThat;