paths: use `list_paths` in `hg paths`
Using common code will make it simpler to update the logic behind the path
definition and storage.
Differential Revision: https://phab.mercurial-scm.org/D10441
Welcome to Mercurial for Windows!
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For configuration and usage directions, please read the ReadMe.html
file that comes with this package.
Also check the release notes at:
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