Update hello module of centos-art.sh script.
    
    - Previously, there was not an option which helps us describe how
      execution of child and sibling modules work. This updates add the
      --camel and --random options to illustrate each of these processes,
      respectively.
    
    - Previously, hello module was using --uppercase and --lowercase
      options. These names were too long so they were reduced to just
      --upper and --lower, respectively.
    
    - Previously, long options hadn't any short option related. This
      update changes the hello_getOptions function to support short
      options, as well.
    
    - Update hello module's documentation manuals to reflect these
      changes.