Support filter-clean filter-smudge, pull, push for large file size in Windows v.s. S3

[zelonght]

With this PR https://github.com/jedbrown/git-fat/pull/28 we can use S3 as Backend.

But we run into limitation of 4GB for file in Windows when running filter-clean and filter-smudge, here is a workaround: https://github.com/PersonifyInc/git-fat/commit/7a1ec1408fac4f902d0596c494294ce66874c590

Then we run into another issue of upload large file to S3 due to S3 limitation of upload single part, here is a solution for it https://github.com/PersonifyInc/git-fat/commit/c026fcf51ed3aca6027401bcd8b68cb6c25bd254

Would be great if we can add S3 support and then those 2 commits to make git-fat support S3 better.

[quangnt]

These solutions are only tested in Windows OS. Note:

• To support filter-clean and filter-smudge work with >= 4GBs file size requires to install Git 64 bit and Windows 64bit.
• To support upload large file size on Windows >=5 GBs, requires to install python library 'filechunkio' by run command pip install filechunkio