Datalad-ukbiobank

- Various updates coping with API deprecations in DataLad.

- Robustified test suite that is more independent of datalad's
specific (but also inconsequential) result reporting behavior.

- The documentation was extended with information on the
`ukbfetch` dependency, and on `ukbfetch_surrogate`.

- Various bits of the code have been adjusted for changes in
DataLad (with no implied change of functionality).

- The test battery has been ported to `pytest` (95% coverage).

- Fixes

- check whether there is a `datalad-archives` special remote,
before attempting to drop from it. Before, the `ukb-update`
would crash for datatype collections that do not contain
any archive. gh-69

- Major documentation update: concepts, procedures, commands

- Fixes

- Improved maintainability. `ukb-update` now runs on a fresh clone
of a dataset that has been initialized with `ukb-init` in the past.
gh-55

- All branches processed by `ukb-update` will now inherit the most
recent state of the main branch's `.gitattributes` file. gh-54

- No longer hard-code the name of the main branch. gh-68

- Minor adjustments for compatibility with DataLad 0.14

- Various substantial issues were fixed:

- Handle non-ZIP file download properly.

- Avoid leakage of absolute paths into the run-record for `ukbfetch`.

- Establish a new "native" layout for (extracted) data records that
makes it possible to properly associate individual files with their
records, even when an original archive does not contain a top-level
directory. gh-29

- Updated BIDS file name mapping.

- A "native" (`incoming-native` branch) and a "bids" layout (`incoming-bids`
branch) are now maintained in parallel by `ukb-update` to support both views
using a single dataset. Enabling the "bids" layout is now done via `ukb-init`.
gh-38

- Added Sphinx-based documentation available at:
http://docs.datalad.org/projects/ukbiobank

- `ukb-update --force-update` was renamed to `ukb-update --force`.

- The `ukb-update` option `--no-bids-dir` was removed.

- `ukb-update` learned to optionally drop extracted archive content or
downloaded archives (`--drop`). Both modes avoid duplication of storage.

- A basic usage description was added to the README.

- A unit test battery was added.

- A keyfile location can now be entered interactively, if not pre-configured.
gh-39

- An example implementation of a faux `ukbfetch` is now included in `tools/`.
Such an implementation can be used to feed already downloaded UKB data
records to this extension.