Fix broken CRLF rule / Check trailing whitespace

- Also removed unused imports

pom.xml

@@ -73,5 +73,23 @@
       <version>5.5</version>
     </dependency>
   </dependencies>
+  
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>2.3.2</version>
+        <configuration>
+          <encoding>UTF-8</encoding>
+          <source>1.6</source>
+          <target>1.6</target>
+          <debug>true</debug>
+          <optimize>true</optimize>
+          <showDeprecation>true</showDeprecation>
+          <showWarnings>true</showWarnings>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
 </project>
 

src/main/java/io/netty/build/checkstyle/SuppressionFilter.java

@@ -20,8 +20,6 @@ import java.util.regex.Pattern;
 import com.puppycrawl.tools.checkstyle.api.AuditEvent;
 import com.puppycrawl.tools.checkstyle.api.AutomaticBean;
 import com.puppycrawl.tools.checkstyle.api.Filter;
-import com.puppycrawl.tools.checkstyle.api.FilterSet;
-import com.puppycrawl.tools.checkstyle.checks.javadoc.JavadocPackageCheck;
 
 public class SuppressionFilter extends AutomaticBean implements Filter {
 
@@ -35,7 +33,7 @@ public class SuppressionFilter extends AutomaticBean implements Filter {
     }
 
     public void setExamplePattern(String pattern) {
-        this.examplePattern = Pattern.compile(pattern);
+        examplePattern = Pattern.compile(pattern);
     }
 
     @Override

src/main/resources/io/netty/checkstyle.xml

@@ -26,19 +26,25 @@
   <module name="NewlineAtEndOfFile">
     <property name="lineSeparator" value="lf" />
   </module>
+  <!-- Copyright headers -->
   <module name="RegexpSingleline">
     <property name="format" value="^(\s|\*)*Copyright\s+[0-9]+\s+The Netty Project\s*$"/>
     <property name="minimum" value="1"/>
     <property name="maximum" value="1"/>
   </module>
+  <!-- Unmaintainable Javadoc tags -->
   <module name="RegexpSingleline">
     <property name="format" value="(@(author|version)|\(non-Javadoc\))"/>
     <property name="ignoreCase" value="true"/>
   </module>
   <!-- Force UNIX line separator -->
-  <module name="RegexpSingleline">
+  <module name="RegexpMultiline">
     <property name="format" value="\r"/>
   </module>
+  <!-- Trailing whitespace -->
+  <module name="RegexpSingleline">
+    <property name="format" value="\s+$"/>
+  </module> 
 
   <module name="TreeWalker">
     <module name="WhitespaceAfter"/>