Adding ewah bool utils

[neutrinoceros]

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[conda-forge-linter]

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

I just wanted to let you know that I linted all conda-recipes in your PR (recipes/ewah-bool-utils) and found it was in an excellent condition.

I do have some suggestions for making it better though...

For recipes/ewah-bool-utils:

• License is not an SPDX identifier (or a custom LicenseRef) nor an SPDX license expression.

Documentation on acceptable licenses can be found here.

[neutrinoceros]

ping @matthewturk

[matthewturk]

What's our best path forward here? We do vendor the underlying EWAH library (in accordance with their license) and I think it's fine if we don't for the purposes of conda, but we will need to pin the version as occasionally upgrading that library has required updating the C++ toolchain etc.

[neutrinoceros]

Reading the fine letters it's actually okay to vendor it as long as we package the license too, which we already do.

[neutrinoceros]

Alright I took a minute to double check and I confirm that we are indeed properly packaging the LICENSE file for the vendored (and modified, as allowed by said license) package.
@matthewturk, do you agree to co-maintain this package with me ? the last thing from the todo list we need is your reply here :)

[matthewturk]

I hereby agree

[neutrinoceros]

@conda-forge/staged-recipes I think this is ready for review