Calc a file's crc
crc_file 0.1.0
USAGE:
crc_file [OPTIONS]
OPTIONS:
-f, --filename <filename>
-o, --offset <offset> offset of the file to read [default: 0]
-l, --length <length> length of the file to read, 0 means read to end of file [default: 0]
-h, --help Print help information
-V, --version Print version information