使用方式：

    1. $ gf pack -h
    2. USAGE
    3.     gf pack SRC DST
    5. ARGUMENT
    6.     SRC  source path for packing, which can be multiple source paths.
    7.     DST  destination file path for packed file. if extension of the filename is ".go" and "-n" option is given,
    8.          it enables packing SRC to go file, or else it packs SRC into a binary file.
    10. OPTION
    11.     -n, --name      package name for output go file, it's set as its directory name if no name passed
    12.     -p, --prefix    prefix for each file packed into the resource file
    14. EXAMPLES
    15.     gf pack public data.bin
    16.     gf pack public,template data.bin
    17.     gf pack public,template packed/data.go
    18.     gf pack public,template,config packed/data.go
    19.     gf pack public,template,config packed/data.go -n=packed -p=/var/www/my-app
    20.     gf pack /var/www/public packed/data.go -n=packed

    该命令用以将任意的文件打包为资源文件或者Go代码文件，可将任意文件打包后随着可执行文件一同发布。此外，在build命令中支持打包+编译一步进行，具体请查看build命令帮助信息。关于资源管理的介绍请参考 资源管理 章节。
    使用示例：

    1. $ gf pack public,template packed/data.go
    2. done!
    3. $ ll packed                             
    4. total 184
    5. -rw-r--r--  1 john  staff    89K Dec 31 00:44 data.go