Fix links and add more info

docs/Upgrade/Upgrade.md

@@ -12,5 +12,5 @@
   - If you use WeKan included Caddy v1, also copy `/var/snap/wekan/common/files/Caddyfile`, but recommended is to use [newer webserver like Caddy 2 etc](../Webserver)
 - [Automatically updating multi Snap](../Platforms/FOSS/Snap/Many-Snaps-on-LXC.md)
   - at multisnap also copy other snapnames like t `/var/snap/wekan_OTHERSNAPNAME/common/files/` to environment variable `WRITABLE_PATH` files subdirectory
-- [Migrate Sandstorm](../Platforms/FOSS/Sandstorm/Export-from-Wekan-Sandstorm-grain-.zip-file.md) also has exporting to JSON textfiles
-- [Migrate text to SQLite and attachments to separate files](https://github.com/wekan/minio-metadata)
+- [Migrate Sandstorm](../Platforms/FOSS/Sandstorm/Export-from-Wekan-Sandstorm-grain-.zip-file.md) that also has [exporting to JSON textfiles](../Platforms/FOSS/Sandstorm/Export-from-Wekan-Sandstorm-grain-.zip-file.md#11b-dump-database-to-json-text-files)
+- [Migrate text to SQLite and attachments to separate files](https://github.com/wekan/minio-metadata) that will be later used with future WeKan versions like [WeKan Studio](https://github.com/wekan/wekanstudio) or [wami](https://github.com/wekan/wami)