fix(download): allow to resume cc_textures download

[gvallicrosa]

Resume cc_textures download when the same output folder is provided. Already downloaded textures are skipped and only missing ones are downloaded.

closes #375 #469

[cla-bot[bot]]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: Guillem Vallicrosa. This is most likely caused by a git client misconfiguration; please make sure to:

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[themasterlink]

This got solved in #658.