Update `texinfo_updateStructureSection.sh':
    
        - Don't reset MANUAL_ENTRY with an empty value here. That would
          supress the value previously defined in `texinfo.sh' file.
    
        - Redesign PATTERN definition using MANUAL_ENTRY and first
          positional paramter as reference. There always be a non-empty
          value for MANUAL_ENTRY and we relay on that to know when
          documentation entry points to manual, chapter or section.
    
        - With these changes and non-option arguments passed to
          `centos-art.sh' script, it is possible to control the amount of
          section entries that will be updated when the
          `--update-structure' option is provided to `centos-art.sh'
          script. You can be specific now.