Merge branch 'cp/unit-test-reftable-block'

Another test for reftable library ported to the unit test framework. * cp/unit-test-reftable-block: t-reftable-block: mark unused argv/argc t-reftable-block: add tests for index blocks t-reftable-block: add tests for obj blocks t-reftable-block: add tests for log blocks t-reftable-block: remove unnecessary variable 'j' t-reftable-block: use xstrfmt() instead of xstrdup() t-reftable-block: use block_iter_reset() instead of block_iter_close() t-reftable-block: use reftable_record_key() instead of strbuf_addstr() t-reftable-block: use reftable_record_equal() instead of check_str() t-reftable-block: release used block reader t: harmonize t-reftable-block.c with coding guidelines t: move reftable/block_test.c to the unit testing framework