MyBatisCursorItemReader

Hi all,

This PR adds a MyBatisCursorItemReader that leverage feature proposed by https://github.com/mybatis/mybatis-3/pull/52.

Unlike MyBatisPagingItemReader, it allows a correct fetch of statements with nested resultmaps. Also, it’s much more efficient since it does only one statement execution at the beginning and keeps the same cursor open until the end.

Usage samples can be found in SpringBatchTest unit test.

Best regards,
Guillaume