Add pyqi requirement under Python2

[nsoranzo]

See https://github.com/biocore/biom-format/blob/2.1.7/setup.py#L129-L130

Also update minimum pandas version.

Add myself as maintainer.

Checklist

• Used a 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 @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 just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[nsoranzo]

Need to move pyqi from bioconda to conda-forge: conda-forge/staged-recipes#6940

[bgruening]

@conda-forge-admin, please rerender

[nsoranzo]

Green, thanks @bgruening !

[bgruening]

Thanks to you!