docs: public Task createDocument(Task task) {
          DocumentRevision rev = new DocumentRevision();
          rev.setBody(DocumentBodyFactory.create(task.asMap()));
          try {
              DocumentRevision created = this.mDocumentStore.database().create(rev);
              return Task.fromRevision(created);
          } catch (DocumentException de) {
              return null;
          } catch (DocumentStoreException de) {
              return null;
          }
      }