Add repodata marker conversion support

[danyeaw]

Description

Closes #275. This PR refactors the marker conversion from our generate_noarch_wheel_repodata.py for the tests to a new markers.py module. It also:

• Adds name mapping to our repodata generation, and refactors name mapping to a new module
• Fixes issues with dotted package names like jaraco.tidelift incorrectly canonicalized as jaraco-tidelift

Since conda doesn't current support [when=...] or [extras=...] MatchSpec syntax, I limited the scope of this PR to not include marker conversion in the translate module for converting wheels to conda packages.

Checklist - did you ...

• Add a file to the news directory (using the template) for the next release's release notes?
• Add / update necessary tests?
• Add / update outdated documentation?

[codspeed-hq]

Merging this PR will degrade performance by 30.45%

❌ 1 regressed benchmark
✅ 4 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	test_build_conda[imagesize]	51.1 ms	73.5 ms	-30.45%

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_{Comparing danyeaw:refactor-markers (f2bcdc3) with main (836a0f3)¹}

Footnotes

1. No successful run was found on main (22bf68d) during the generation of this report, so 836a0f3 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩