added link to v0.0.0

Author: ect123

index.md

@@ -72,3 +72,7 @@ A [converter](https://openindexmaps.org/converter) is available for converting s
 ### Tutorial
 
 A [Creating GeoJSON for OpenIndexMaps](https://kgjenkins.github.io/openindexmaps-workshop/) tutorial was created for a workshop at Geo4LibCamp 2020. The tutorial works through several examples of using QGIS to create OpenIndexMaps GeoJSON files.
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+## Legacy Version
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+[OpenIndexMap Version 0](/specification/0.0.0)