update plugin versions

Author: igdianov

pom.xml

@@ -216,7 +216,7 @@
       <!-- Required: javadoc JAR -->
       <plugin>
         <artifactId>maven-javadoc-plugin</artifactId>
-        <version>3.6.2</version>
+        <version>2.9.1</version>
         <configuration>
           <source>${java.version}</source>
         </configuration>
@@ -246,7 +246,7 @@
       <!-- Required: source JAR -->
       <plugin>
         <artifactId>maven-source-plugin</artifactId>
-        <version>3.3.0</version>
+        <version>2.2.1</version>
         <executions>
           <execution>
             <id>attach-sources</id>
@@ -398,7 +398,7 @@
             <configuration>
               <serverId>sonatype-nexus-staging</serverId>
               <nexusUrl>https://oss.sonatype.org/</nexusUrl>
-              <autoReleaseAfterClose>true</autoReleaseAfterClose>
+              <autoReleaseAfterClose>false</autoReleaseAfterClose>
               <skipStaging>${skipStaging}</skipStaging>
             </configuration>
           </plugin>
@@ -420,7 +420,7 @@
           <plugin>
             <groupId>org.apache.maven.plugins</groupId>
             <artifactId>maven-gpg-plugin</artifactId>
-            <version>3.1.0</version>
+            <version>3.0.1</version>
             <executions>
               <execution>
                 <id>sign-artifacts</id>