rspotify 0.16.0

Spotify API wrapper
Documentation
## Description

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## Motivation and Context

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## Dependencies 

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## Type of change

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- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
- [ ] This change requires a documentation update

## How has this been tested?

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- [ ] Test A: xxx
- [ ] Test B: xxx

## Is this change properly documented?

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Don't forget to add an entry to the CHANGELOG if necessary (new features, breaking changes, relevant internal improvements).