How to release.

    <profile>
      <id>apache-release</id>
      <build>
        <plugins>
          <!-- Create a source-release artifact that contains the fully buildable
               project directory source structure. This is the artifact which is
               the official subject of any release vote. -->
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-assembly-plugin</artifactId>
            <dependencies>
              <dependency>
                <groupId>org.apache.apache.resources</groupId>
                <artifactId>apache-source-release-assembly-descriptor</artifactId>
                <version>1.0.6</version>
              </dependency>
            </dependencies>
            <executions>
              <execution>
                <id>source-release-assembly</id>
                <phase>package</phase>
                <goals>
                  <goal>single</goal>
                </goals>
                <configuration>
                  <runOnlyAtExecutionRoot>true</runOnlyAtExecutionRoot>
                  <descriptorRefs>
                    <descriptorRef>${sourceReleaseAssemblyDescriptor}</descriptorRef>
                  </descriptorRefs>
                  <tarLongFileMode>gnu</tarLongFileMode>
                </configuration>
              </execution>
            </executions>
          </plugin>
          <!-- We want to deploy the artifact to a staging location for perusal -->
          <plugin>
            <inherited>true</inherited>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-deploy-plugin</artifactId>
            <configuration>
              <updateReleaseInfo>true</updateReleaseInfo>
            </configuration>
          </plugin>
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-source-plugin</artifactId>
            <executions>
              <execution>
                <id>attach-sources</id>
                <goals>
                  <goal>jar-no-fork</goal>
                </goals>
              </execution>
            </executions>
          </plugin>
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-javadoc-plugin</artifactId>
            <executions>
              <execution>
                <id>attach-javadocs</id>
                <goals>
                  <goal>jar</goal>
                </goals>
              </execution>
            </executions>
          </plugin>
          <!-- We want to sign the artifact, the POM, and all attached artifacts -->
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-gpg-plugin</artifactId>
            <executions>
              <execution>
                <id>sign-release-artifacts</id>
                <goals>
                  <goal>sign</goal>
                </goals>
              </execution>
            </executions>
          </plugin>
        </plugins>
      </build>
    </profile>