Authentication and documentation improvements

What's Changed

• chore: add repository topics and SEO heading by @vsaez in #59
• Enforce user OAuth tokens and safer refresh handling by @vsaez in #62
• Feat/automatic spotify oath flow by @vsaez in #68
• Feat/automatic spotify oath flow by @vsaez in #69
• Remove impoved_readme.md by @vsaez in #70
• feat/include hero gif by @vsaez in #71
• Changes references of github by @vsaez in #72
• Add badges by @vsaez in #73

Full Changelog: v0.1.0...v0.2.0