Add name member to Database interface.

Looking at the PouchDB source, this member is always set[1] (earlier in that function we throw if the name is not a string).

[1] https://github.com/pouchdb/pouchdb/blob/master/packages/node_modules/pouchdb-core/src/constructor.js#L68

types/pouchdb-core/index.d.ts

@@ -581,6 +581,9 @@ declare namespace PouchDB {
     }
 
     interface Database<Content extends {} = {}>  {
+        /** The name passed to the PouchDB constructor and unique identifier of the database. */
+        name: string;
+
         /** Fetch all documents matching the given options. */
         allDocs<Model>(options?: Core.AllDocsWithKeyOptions | Core.AllDocsWithKeysOptions | Core.AllDocsWithinRangeOptions | Core.AllDocsOptions):
             Promise<Core.AllDocsResponse<Content & Model>>;