Changes

Summary

1. tidy up playlisteditscreen (details)
2. Add UrlExt function to separate a school endpoint url from the rest of any link. (details)
3. updated eraseText (details)
4. Update datalayer README to add conceptual notes on data deletion. (details)
5. Fix UrlExt.schoolUrlOrNull function. (details)
6. Add normalization for school endpoint URL. (details)

tidy up playlisteditscreen

Add UrlExt function to separate a school endpoint url from the rest of any link.

updated eraseText

Update datalayer README to add conceptual notes on data deletion.

Fix UrlExt.schoolUrlOrNull function.

Add normalization for school endpoint URL.