The database watcher always uses couchdb_database_get_document to check whether documents still exist

The database watcher uses couchdb_database_get_document to retrieve an instance of the document in dbwatch.c:process_change.

This function cannot be used to retrieve design documents, since it uses the format string "%s/%s/%s" with the CouchDB session URI, the database name and the encoded document ID. Design documents contain a slash, which is escaped although it should not.

I have attached a patch that adds a fallback in couchdb_database_get_document---if the ID begins with "_design/", couchdb_database_get_design_document is called instead.