v1.3.0

Better support for using composite primary keys:

• New enum in this crate: tables::PrimaryKey
  • Single(String): let single: PrimaryKey = "hello world".into()
  • Composite(BTreeMap<String, String>): let composite: PrimaryKey = [("evt_tx_hash","hello".to_string()),("evt_index","world".to_string())].into()

Breaking changes:

• The Rows.pks field is not public anymore.
• create_row(), update_row() and delete_row() now require a PrimaryKey instead of a String. This should work directly with a String, &String or &str.