AVR8 support in vsprog

Information:
    Vsprog can support AVR8 in ISP/JTAG interfaces.
    Auto-detect feature is supported on AVR8.
    Supported target area: flash('f'), lock('l'), fuse('u'), calibration('c', read-only).

Vsprog options:
    -savr8, refer to -s option.
    -c, refer to -c option.
    -m, refer to -m option. Supported modes:
        i: ISP mode, default
        j: JTAG mode
    -F, refer to -F option. This option is used to define frequency of ISP/JTAG, default value for ISP is 560, default value for JTAG is 4500, unit: kHz.
    -t, refer to -t option. Target area defined by -t option is lock and fuse.