test_git_extract_cache_quick_across_migration_threshold
[lib/git.rb] git_extract was hard coded to use ext4
update cache status to match latest kernel
test_fio_soak_test
add fio.config
a few bcache tests - notably Darrick's "database-funtime"

These bcache tests need to be placed elsewhere (along with other
test-suite cleanup) but this is what I slapped together.
rename test_fio_soak_test to test_fio_sub_volume_scenario.

Implement for EnhanceIO.

There's now a separate EnhanceIO suite.

./run_tests --suite enhance_io -n test_fio_sub_volume --profile mix
reset to match ejt's thinp-test-suite
add missing files
add bcache suite and some other cleanup

also adds tests that use database-funtime.fio
Merge remote branch 'ejt/master' into devel
Merge branch 'bcache' into devel
Merge remote branch 'origin/devel' into devel
remove the test_writethrough_ext4_uuids_match changes

we have coverage through joe's test