Backport windows to 2020.2

[isuruf]

This reverts commit 54e23d25d2ec77f2492038eb31db067077089038, reversing changes made to 50ed5353d18b5e90ad188061eaf90d9bcd7a393a.

Checklist

• [ ] Used a personal fork of the feedstock to propose changes
• [ ] Bumped the build number (if the version is unchanged)
• [ ] Reset the build number to 0 (if the version changed)
• [ ] Re-rendered with the latest conda-smithy (Use the phrase code>@<space/conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• [ ] Ensured the license file is being packaged.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I wanted to let you know that I linted all conda-recipes in your PR (recipe) and found some lint.

Here's what I've got...

For recipe:

• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).
• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).
• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).
• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).
• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).
• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).
• When defining a source/url please add a sha256, sha1 or md5 checksum (sha256 preferably).

[beckermr]

We should explain why in the PR text here so we don't forget later.

[isuruf]

Because we are still using this version in blas-feedstock and channel priority removes the 2020.2 from defaults because we have only 2020.4

[beckermr]

Awesome thank you! LGTM when you are happy!

[napetrov]

@isuruf can we keep MKL on 2020.2 but still update daal to 2020.3?

[isuruf]

Oops. I meant to merge this to a branch instead of master. I fixed it. master is on 2020.3 and there's a 2020.2 branch