support writing to data chunks

[jraymakers]

• Support writing to vectors of all types.
• Add convenience methods for writing to data chunks.
• Add convenience methods for creating types, as well as convenience getters for important values of each type.
• Add way to get a DuckDBLogicalType from a DuckDBType.
• Refactor data for test_all_types so it can be shared with appender tests.
• Add many tests for writing vectors, data chunks, and appending data chunks, including an "append all data types" test.
• To support the above, add two new functions to the bindings layer, for writing data to vector and validity buffers.