Draft: API: remove UniqueResult, lower-case at, size for ResultSet

Summary

• Remove UniqueResult
• At and Size are lower-case now (ResultSet, MultiResultSet)

include/ccaosdb.h

@@ -251,6 +251,8 @@ int caosdb_transaction_transaction_retrieve_by_id(
   caosdb_transaction_transaction *transaction, const char *id);
 int caosdb_transaction_transaction_retrieve_by_ids(
   caosdb_transaction_transaction *transaction, const char *ids[]);
+int caosdb_transaction_transaction_query(
+  caosdb_transaction_transaction *transaction, const char *query);
 int caosdb_transaction_transaction_execute(
   caosdb_transaction_transaction *transaction);
 // TODO(fspreck) execute_asynchronously may be added as a separate