Vak

Added
- Use `attrs`-based classes to represent sections of config.ini files

Changed
- rewrite `vak.cli` so it can deal with state of config.ini files
+ e.g. doesn't throw an error if `train_data_path` not declared as an option in [TRAIN] when running `vak prep`
(since training data won't exist yet, doesn't make sense to throw an error).

Removed
- remove code about `freq_bins` in a couple of places, since the number of frequency bins
in spectrograms is now just determined programmatically
+ `vak.config.data` no longer has `freq_bins` field in DataConfig namedtuple
+ `make_data` no longer adds `freq_bins` option to [DATA] section after making data sets

Fixed
- add missing 'save_transformed_data' option to Data config parsing

Changed
- checkpoints saved in individual directories by `learncurve` so they are more cleanly segregated,
e.g. if user wants to point to a specific checkpoint when calling `predict`
- calling `vak prep config.ini` will run `vak.cli.make_data` function
+ so to generate a learning curve, the three steps now are:
bash
vak prep config.ini
vak learncurve config.ini
vak summary config.ini


Fixed
- `vak.cli.train` runs all the way through, passes basic "does not crash" test
- `vak.cli.predict` runs all the way through, passes basic "does not crash" test

Changed
- description in setup.py (matches README + Github)
- move command-line interface logic out of __main__.py, into cli/cli.py
- `make_data` and `learncurve` functions use `tqdm` for progress bars

Fixed
- main() knows to look for `configfile` command-line argument (not `config`)
- `config` module expands user (on Linux/Mac) for (some) directory names

First release; still in pre-release
Changed
- name change from 'songdeck' to 'vak'