remove unnecessary imports (are not used)

Change-Id: I60db0b50c786d83cd66e786a727c677902da5998
diff --git a/src/main/java/de/ids_mannheim/korap/plkexport/ExWSConf.java b/src/main/java/de/ids_mannheim/korap/plkexport/ExWSConf.java
index 864100e..ec1886a 100644
--- a/src/main/java/de/ids_mannheim/korap/plkexport/ExWSConf.java
+++ b/src/main/java/de/ids_mannheim/korap/plkexport/ExWSConf.java
@@ -11,8 +11,6 @@
 import java.io.*;
 import java.lang.String;
 import java.util.Properties;
-import java.nio.charset.StandardCharsets;
-
 import org.tinylog.Logger;
 
 public class ExWSConf {
diff --git a/src/main/java/de/ids_mannheim/korap/plkexport/Exporter.java b/src/main/java/de/ids_mannheim/korap/plkexport/Exporter.java
index c779cc1..5c27b85 100644
--- a/src/main/java/de/ids_mannheim/korap/plkexport/Exporter.java
+++ b/src/main/java/de/ids_mannheim/korap/plkexport/Exporter.java
@@ -1,7 +1,6 @@
 package de.ids_mannheim.korap.plkexport;
 
 import com.fasterxml.jackson.databind.JsonNode;
-import javax.ws.rs.core.Response;
 import javax.ws.rs.core.Response.ResponseBuilder;
 import java.io.IOException;
 import java.io.Writer;
diff --git a/src/main/java/de/ids_mannheim/korap/plkexport/MatchAggregator.java b/src/main/java/de/ids_mannheim/korap/plkexport/MatchAggregator.java
index 8aa283d..95c2b2e 100644
--- a/src/main/java/de/ids_mannheim/korap/plkexport/MatchAggregator.java
+++ b/src/main/java/de/ids_mannheim/korap/plkexport/MatchAggregator.java
@@ -10,15 +10,10 @@
 import java.io.OutputStream;
 import java.io.FileInputStream;
 
-import java.util.Collection;
-import java.util.ArrayList;
 import java.util.Iterator;
-import java.util.LinkedList;
 import java.util.Properties;
 
-import com.fasterxml.jackson.core.JsonFactory;
 import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.core.Version;
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
diff --git a/src/main/java/de/ids_mannheim/korap/plkexport/PluginServer.java b/src/main/java/de/ids_mannheim/korap/plkexport/PluginServer.java
index c1127e9..ca0c4c9 100644
--- a/src/main/java/de/ids_mannheim/korap/plkexport/PluginServer.java
+++ b/src/main/java/de/ids_mannheim/korap/plkexport/PluginServer.java
@@ -1,12 +1,10 @@
 package de.ids_mannheim.korap.plkexport;
 
-import java.io.File;
 import java.util.Properties;
 
 import org.eclipse.jetty.server.Handler;
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.server.ServerConnector;
-import org.eclipse.jetty.server.handler.ContextHandler;
 import org.eclipse.jetty.server.handler.DefaultHandler;
 import org.eclipse.jetty.server.handler.HandlerList;
 import org.eclipse.jetty.servlet.ServletContextHandler;
diff --git a/src/main/java/de/ids_mannheim/korap/plkexport/RtfExporter.java b/src/main/java/de/ids_mannheim/korap/plkexport/RtfExporter.java
index c3655ef..6a7f279 100644
--- a/src/main/java/de/ids_mannheim/korap/plkexport/RtfExporter.java
+++ b/src/main/java/de/ids_mannheim/korap/plkexport/RtfExporter.java
@@ -2,8 +2,6 @@
 
 import java.util.Properties;
 
-import java.lang.StringBuffer;
-
 import java.nio.charset.*;
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
@@ -17,8 +15,6 @@
 import java.io.IOException;
 import java.io.Writer;
 
-import de.ids_mannheim.korap.plkexport.Util.*;
-
 /**
  * Streaming RTF exporter.
  */
diff --git a/src/main/java/de/ids_mannheim/korap/plkexport/Service.java b/src/main/java/de/ids_mannheim/korap/plkexport/Service.java
index 2ef6338..b57667a 100644
--- a/src/main/java/de/ids_mannheim/korap/plkexport/Service.java
+++ b/src/main/java/de/ids_mannheim/korap/plkexport/Service.java
@@ -1,17 +1,10 @@
 package de.ids_mannheim.korap.plkexport;
 
-import java.io.BufferedWriter;
-import java.io.File;
-import java.io.FileWriter;
 import java.io.IOException;
 import java.io.StringWriter;
 import java.io.InputStream;
 import java.lang.Thread;
-import java.net.URLEncoder;
-import java.net.ConnectException;
 import java.util.HashMap;
-import java.util.Collection;
-import java.util.Iterator;
 import java.util.Properties;
 import java.util.Base64;
 import java.util.ResourceBundle;
@@ -19,7 +12,6 @@
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
-import javax.ws.rs.BadRequestException;
 import javax.ws.rs.WebApplicationException;
 import javax.ws.rs.FormParam;
 import javax.ws.rs.QueryParam;