Update `identity' functionality:
    
        - Rename command-line interface options:
    
            from                to
            ---------------     --------------
            --release           --releasever
            --architecture      --basearch
    
        - Add the following options to command-line interface to be
          process as post-rendition actions:
    
            option              description
            ---------------     --------------
            --convert-to        to convert final PNG output to different image formats.
            --grouped-by        to group similar image files into directories.
    
            These options were used in pre-rendition configuration
            scripts, but now pre-rendition configuration script are no
            longer used.
    
        - Do not use pre-rendition configuration scripts anymore. Instead,
          use command-line options and directory-specific processing to
          execute post-rendition and last-rendition actions.
    
        - Merge identity_getConfig.sh into identity_render functionality.
          Specifically, inside identity_renderSvgPostActions and
          identity_renderSvgLastActions to implement directory-specific
          processing of post-rendition and last-rendition actions. 
          
        - Remove identity_getConfig.sh.