Format a string into/out of base64
    -i : in to base64 (default)
    -o : out of base64
    -w : line length for formatting to base64
        default is -w 0 for NO end-of-line
    -h : do not process the FipHdr if it exists
        default is to take the whole file as data
    -s : optional input string
    -v : version and exit

    sffb64 -i -s "mylogon:mypwd"
    echo -n "zibble/bongo" | sffb64 -i > /tmp/formattedbase64
    cat MyBase64StringFile | sffb64 -o > /tmp/cleartext

Normally, for into base64, we add a NewLine After the string, use the '-n'
input switch to strip.

Note that if you use 'echo' pls remember to NOT add a NL at the end.

Only other input parameter is -v : version and exit

Version Control
;000i    5dec97 chris original version
    ;a  1oct98 buffer size up pls
    ;b 10mar00 bugette
    ;c 29jan02 added -w, -h
    ;d 04aug03 mini mod to decode
    ;e-i 08feb07 bugette - adding an extra '=' pad at end.

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