Dtool

---------------------

Added support for tags.

Added
^^^^^

- Added ``dtool_irods.storagebroker.IrodsStorageBroker.delete_key()`` method
- Added ``dtool_irods.storagebroker.IrodsStorageBroker.get_tag_key()`` method
- Added ``dtool_irods.storagebroker.IrodsStorageBroker.list_tags()`` method

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Fixed
^^^^^

- Fixed defect where old dataset that predated the concept of annotations
failed to copy from iRODS because it expected an annotations collection to
exist in iRODS

--------------------

Fixed
^^^^^

- Fixed defect introduced during code refactoring in 0.9.0 that resulted in
iRODS command being able to fail silently when they should have been
complaining loudly

--------------------

Added
^^^^^

- Added support for dataset annotations

Fixed
^^^^^

- Improved way in which iRODS authentication timeout messages are reported back
to end users

--------------------

Added
^^^^^

- Added optimisation to improve speed when copying data from iRODS

--------------------

Changed
^^^^^^^

- Cache environment variable changed from DTOOL_IRODS_CACHE_DIRECTORY to DTOOL_CACHE_DIRECTORY
- Default cache directory changed from ``~/.cache/dtool/irods`` to ``~/.cache/dtool``