Update the locale module of centos-art.sh script.
    
    - Previously, some of the most important module environment variables
      were defined in the ${MODULE_NAME}.conf.sh file. Using the
      ${MODULE_NAME}.conf.sh file was discontinued a few days ago and
      variables inside them were undefined making the locale module to
      fail. This update changes ${MODULE_NAME}.sh files to initialize
      module environment variables in them making the locale module to
      work as expected.
    
    - Previously, we were using tcar_setModuleEnvironment function to load
      both modules and submodules inside centos-art.sh script without any
      different. Now, because we want to load first-level modules from
      sub-modules, we use tcar_setModuleEnvironment to load first-level
      modules only and tcar_setSubModuleEnvironment to load sub-modules at
      different levels only. This update changes the files inside the
      locale module to start using both tcar_setModuleEnvironment and
      tcar_setSubModuleEnvironment functions when loading first-level
      modules and sub-modules.
    
    - Inside locale.sh and locale_getOptions.sh, rename variable from
      ACTIONS to SUBMODULES.
    
    - Previously, we were using the ${MODULE_NAME}.asciidoc file name in
      documentation manuals. This might bring confusion with other
      commands outside centos-art.sh script. So, to avoid such confusion,
      this udpate changes the documentation manual file name from
      ${MODULE_NAME}.asciidoc to centos-art.sh-${MODULE_NAME}.asciidoc.
    
    - Remove locale.sh.asciidoc and locale.conf.sh.asciidoc files from
      documentation manuals. Environment information will be handle inside
      centos-art.sh-locale.asciidoc documentation manual.