Add an option support to normalize path

[fuweichin]

I prepared a json file .oss-sync.json:

{
    "endpoint":"...",
    "accessKeyId":"...",
    "secretAccessKey":"...",
    "bucket":"sda1",
    "source":"/Users/Administrator/Buckets/sda1/images",
    "dest":"images"
}

Then when those done

cd /Users/Administrator/Buckets/sda1
mv camomile-960x600.jpg images/camomile-960x600.jpg
osync

One file was uploaded and I got images\camomile-960x600.jpg through Aliyun OSS web console, which is not the one what I expected, since I use Windows OS and the web console doesn't recognize key images\camomile-960x600.jpg as a directory and a file.

So my proposal is to add an option support in oss-sync json config file in order to normalize path, as but not limited to

{
    ...
    "normalizePath":true
}

Thus path will be normalized as option normalizePath is set to true, and I may get a directory "images", and a file "camomile-960x600.jpg" under the directory, through the web console.

[mehwww]

Sorry i'm not familiar with node on Windows, and I think this is a bug related to Windows file system or git on Windows but not a option problem.

I would appreciate that if someone can make a PR about this issue or have to find a PC with git and node to solve this when i have time