Add ruby-terminfo dependency

Rerun bundle
Add --tags switch to 'list' command
Give an error message if the suite isn't specified.
[thinp] test_thin_remove_works_after_resize
[era target] run era_check on teardown
[era] test_wiped_blocks_have_increasing_eras

This need more work, since it relies on manual inspect of the dumped metadata atm.
work on era tests
FIx bug in with_mount

It wasn't propagating exceptions up.
rollback previous commit
[era] Move test_wiped_blocks_have_increasing_eras to it's own file, and improve
[era] EraStatus class
fluff
[era] Add EraStack#checkpoint

This sends the checkpoint message and retrieves the current era via
the status.
[era] test_many_eras_does_not_exhaust_metadata
[cache] lift cache_utils, cache_policy and cache_stack to dmtest so I can use in the era tests
[era] Lift era_stack, era_utils, era_status
[era] era tracking tests
update dm cache status parsing
update dm cache status parsing to handle policy_name

update test_status to verify that "default" policy is reported as "mq"
in the cache status -- brittle if we alter which policy is the "default"
but...
cant_provision_new_blocks must use error_if_no_space

otherwise the wipe_device to the thin device will hang