The additional components are built using the extras.xml Ant script which is
      present in the source bundle of Tomcat.
    
    
    The build process is the following:
    
    
    - Follow the build instructions to build a Tomcat binary from
    the source bundle (note: it will be used by the build process of the additional components, but
    does not need to be actually used later on)
 
    - Execute the command 
ant -f extras.xml to run the build script 
    - The additional components JARs will be placed in the 
output/extras folder 
    - Refer to the documentation below about the usage of these JARs