Update variable name space inside tcar-scripts.
    
    - Previously, TCAR_SCRIPT_NAME variable was set define the script name
      as "tcar.sh". This update removes the TCAR_SCRIPT_NAME variable and
      uses TCAR_SCRIPT_PACKAGE variable instead which is set to "tcar".
    
    - Previously, TCAR_SCRIPT_COMMAND variable was set to define the
      script command as "tcar". This update removes TCAR_SCRIPT_NAME
      variable and uses TCAR_SCRIPT_PACKAGE variable instead, which is set
      to "tcar" as well.