Add partial support for pathlib.Path objects in raster and vector modules __Status: Review Needed__

[remtav]

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Description

Add partial support for pathlib.Path objects in raster and vector modules

Fixes # (issue)

Type of change

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• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected - these changes will not be merged until major releases!)

How Has This Been Tested?

Please describe tests that you added to the pytest codebase (if applicable).

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• [x] My PR has a descriptive title
• [x] My code follows PEP8
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[rbavery]

@remtav thanks for your contribution! I and my colleagues at Development Seed are taking on maintainership of this library. Work is ongoing in https://github.com/CosmiQ/solaris/pull/436 to focus this library's scope, see https://github.com/CosmiQ/solaris/blob/32236217bd913fbb238e19f2f8420e5794fd8136/ROADMAP.md for details. This sounds like a valuable PR that would make sense to be introduced after a .5 release, feel free to resubmit this PR or request this PR be re-opened after .5 is released.