Epic-kitchens

Changes

* Default path to download files is `~/.cache/epic-kitchens` instead of
`~/epic-kitchens`

Features

* Add `epic_kitchens.metrics` and `epic_kitchens.scoring` containing method for
computing metrics and manipulating model scores. Of particular note is
`epic_kitchens.metrics.compute_metrics` which computes top-{1,5} accuracy,
many-shot precision and recall for the verb, noun and action prediction tasks.

Dependencies

* We now depend on `scikit-learn` for computing metrics.

Dependencies
* Depend on `moviepy` >= 1.0.0 due to `imageio` breaking `ffmpeg` download
capabilities.

Bug fix

* `epic_kitchens.gulp.visualisation` visualisers returned `ImageSequenceClip`
instead of IPython HTML display element, which caused the videos not to show
up in Jupyter, these methods now return an `IPython.display.HTML` element
* Fix bug in `epic_kitchens.gulp.visualisation.combine_flow_uv_frames` where
`hstack_frames` wasn't called with `width_axis` correctly causing a
RuntimeError

Bug fix

* Add sphinx 1.8.2 to requirements.txt to get RTFD to build the docs

Features

* Add `epic_kitchens.meta` package containing helpers for downloading and reading
label class definitions, and training and test set annotations.
* Add `epic_kitchens.data.visualisation` package containing tools that allow you
to view arbitrary action segments RGB or Flow contained in a `EpicVideoDataset`
using `moviepy`. This is useful when sifting through results per instance.

Changes
* Improve documentation and bring it all in line with google doc string
standards