feat!: update module options

[DamianGlowala]

🔗 Linked issue

resolves #59

❓ Type of change

• 📖 Documentation (updates to the documentation, readme or JSDoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This adds initMode option and changes the purpose of enabled one.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

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[johannschopplich]

Great idea. Let's wait until this module has been moved to the @nuxtjs namespace. After the migration, I will release a new major version.

[DamianGlowala]

Sure!

When working on this PR, I was wondering whether it would make sense for this module to expose isInitialized flag (the one which currently is declared in the playground? Let me know if it would bring any value and I can add it :)

[johannschopplich]

Yeah, absolutely! Would be a great addition to check if one (or multiple) IDs have been activated already.