Managed Synonyms should support deleting all synonyms or replacing a single one

Currently it is only possible to add synonyms and deleting single synonyms. If you need to delete all synonyms you have to get the list and then sending an delete request to every single synonym. Also you can't overwrite a synonym but only append it.

It would be more convenient to have additional possibilities:

Deleting all synonyms
curl -XDELETE http://localhost:8983/solr/collection1/schema/analysis/synonyms/english/

Overwriting a single synonym
curl -XPUT http://localhost:8983/solr/collection1/schema/analysis/synonyms/english/apple

Add a synonym / append to an existing synonym
curl -XPOST http://localhost:8983/solr/collection1/schema/analysis/synonyms/english/apple