Add antialiasing option to Resample and RandomAffine

[fepegar]

As in NifTK/NiftyNet@a91644b#diff-5b79901b7b2f56394aca30c562e9e186

[sairampillai]

Hey @fepegar. I would like to contribute. Would this be a good issue to start with? Any other details regarding this issue?

[fepegar]

Hi @sairampillai. Thanks for your interest!
Yes, this might be a good one. I had in mind something like what I did for NiftyNet:

https://github.com/NifTK/NiftyNet/blob/7421b013e5d7852f2eab1861de0bc768995ec82b/niftynet/layer/rand_spatial_scaling.py#L67-L73

You can start by

1. Fork this repo
2. Create a branch 48-add-antialiasing on the fork
3. Commit your changes to that branch
4. Submit a pull request to this repo, even if it's not ready

I'll review the commits and merge your changes.

Thank you!