ZOOKEEPER-3351: Fix findBugs and rat check, add filename to sha

Note: this is only for master, for 3.5 branch it needs a different PR!
Correction: I will test this on 3.5 branch first!

Author: Norbert Kalmar <nkalmar@yahoo.com>

Reviewers: andor@apache.org

Closes #907 from nkalmar/ZK-3351 and squashes the following commits:

ca7715321 [Norbert Kalmar] ZOOKEEPER-3351 - fix findBugs issue on released versions
161df0b21 [Norbert Kalmar] ZOOKEEPER-3351 - add rat exceptions and fix sha generation

pom.xml

@@ -681,6 +681,7 @@
           <algorithms>
             <algorithm>SHA-512</algorithm>
           </algorithms>
+          <appendFilename>true</appendFilename>
         </configuration>
       </plugin>
 
@@ -699,6 +700,43 @@
           </suppressionFiles>
         </configuration>
       </plugin>
+      <plugin>
+        <groupId>org.apache.rat</groupId>
+        <artifactId>apache-rat-plugin</artifactId>
+        <configuration>
+          <excludes>
+            <exclude>**/log4j.properties</exclude>
+            <exclude>**/README.md</exclude>
+            <exclude>**/git.properties</exclude>
+            <exclude>**/findbugsExcludeFile.xml</exclude>
+            <exclude>**/checkstyle-noframes-sorted.xsl</exclude>
+            <exclude>**/configure.ac</exclude>
+            <exclude>**/Makefile.am</exclude>
+            <exclude>conf/zoo_sample.cfg</exclude>
+            <exclude>conf/configuration.xsl</exclude>
+            <exclude>.travis.yml</exclude>
+            <exclude>excludeFindBugsFilter.xml</exclude>
+            <exclude>README_packaging.txt</exclude>
+            <exclude>src/main/resources/markdown/skin/*</exclude>
+            <exclude>src/main/resources/markdown/html/*</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-loggraph/src/main/resources/webapp/org/apache/zookeeper/graph/resources/*</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-zooinspector/TODO</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-zkperl/Changes</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-zkperl/MANIFEST</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-fatjar/src/main/resources/mainClasses</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-monitoring/JMX-RESOURCES</exclude>
+            <exclude>zookeeper-contrib/zookeeper-contrib-zooinspector/src/main/java/com/nitido/utils/toaster/Toaster.java</exclude>
+            <exclude>**/acinclude.m4</exclude>
+            <exclude>**/aminclude.am</exclude>
+            <exclude>zookeeper-client-c/src/hashtable/*</exclude>
+            <exclude>zookeeper-client-c/include/winconfig.h</exclude>
+            <exclude>zookeeper-client-c/tests/wrappers.opt</exclude>
+            <exclude>zookeeper-client-c/tests/quorum.cfg</exclude>
+            <exclude>zookeeper-client-c/tests/wrappers-mt.opt</exclude>
+            <exclude>**/c-doc.Doxyfile</exclude>
+          </excludes>
+        </configuration>
+      </plugin>
     </plugins>
 
     <resources>

zookeeper-server/src/main/java/org/apache/zookeeper/Version.java

@@ -18,6 +18,7 @@
 
 package org.apache.zookeeper;
 
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import org.apache.zookeeper.server.ExitCode;
 
 public class Version implements org.apache.zookeeper.version.Info {
@@ -41,6 +42,8 @@ public class Version implements org.apache.zookeeper.version.Info {
         return BUILD_DATE;
     }
 
+    @SuppressFBWarnings(value = "RCN_REDUNDANT_NULLCHECK_OF_NULL_VALUE",
+            justification = "Missing QUALIFIER causes redundant null-check")
     public static String getVersion() {
         return MAJOR + "." + MINOR + "." + MICRO
             + (QUALIFIER == null ? "" : "-" + QUALIFIER);