fix jrcs imports (#2289)

fixes #2288

Author: Vladimir Kotal

opengrok-web/src/main/webapp/diff.jsp

@@ -32,8 +32,8 @@ java.io.UnsupportedEncodingException,
 java.net.URLDecoder,
 java.util.ArrayList,
 
-org.suigeneris.jrcs.diff.Chunk,
-org.suigeneris.jrcs.diff.Delta,
+org.suigeneris.jrcs.diff.delta.Chunk,
+org.suigeneris.jrcs.diff.delta.Delta,
 org.suigeneris.jrcs.diff.Diff,
 org.suigeneris.jrcs.diff.Revision,
 org.opengrok.indexer.analysis.AnalyzerGuru,