Forked 2.0.0: Java 11 Support

This release is a tag of the final version of the Java 11 support PR: asciidoctor#96

Use this by downloading the asciidoclet-2.0.0-shaded.jar file, vendor it into your repository, and refer to it via the docletPath.

Here is an example of how to do this in your pom.xml, assuming you have saved the above jar file in a build directory:

    <build>
      ...
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-javadoc-plugin</artifactId>
        <version>${javadoc.version}</version>
        <executions>
          <execution>
            <id>attach-javadocs</id>
            <goals>
              <goal>jar</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <additionalJOptions>
            <additionalJOption>-J--add-exports=jdk.javadoc/jdk.javadoc.internal.tool=ALL-UNNAMED</additionalJOption>
            <additionalJOption>-Xdoclint:all,-html,-accessibility</additionalJOption>
            <additionalJOption>--base-dir</additionalJOption>
            <additionalJOption>${project.basedir}</additionalJOption>
          </additionalJOptions>
          <doclet>org.asciidoctor.asciidoclet.Asciidoclet</doclet>
          <detectJavaApiLink>true</detectJavaApiLink>
          <docletPath>${project.basedir}/build/asciidoclet-2.0.0-shaded.jar</docletPath>
        </configuration>
      </plugin>