Chainerui

**Note that this is planned to be the final major release.** As [announced in chainer blog](https://chainer.org/announcement/2019/12/05/released-v7.html), further development will be limited to only serious bug-fixes and maintenance.

New features

* Add simple filtering UI for experiments table (301, 332)
* <img src="https://user-images.githubusercontent.com/4876459/67649333-02380f00-f97c-11e9-9238-d03ef35f97af.png" width="500px">
* Bulk delete and restore results (322, 334, 335)
* <img src="https://user-images.githubusercontent.com/4876459/65650595-8bd78280-e046-11e9-9b6f-9df991db3a12.png" width="500px">
* <img src="https://user-images.githubusercontent.com/4876459/65650599-8e39dc80-e046-11e9-9605-a51b17e10547.png" width="500px">
* Line Smoothing (333)
* <img src="https://user-images.githubusercontent.com/280562/68010930-44898500-fcc9-11e9-97bb-d6d7c18bdf05.png" width="500px">
* Undo button for updated results (344)
* <img src="https://user-images.githubusercontent.com/4876459/71226131-241b9580-231e-11ea-91ff-69b8dd76e678.png" width="500px">

Improvements

* Support ignite handler (327)
* Reorganize examples and update docs (337)

Bug fix, refactoring

* Introduce doctest (324)
* Reduce py2 test menu on CI (330)
* Handling empty log (331)
* Rewrite by TypeScript (321, 328, 340, 343)
* Split actions and reducers into files (339)
* Fix to generate docs (336)

hotfix, 317

New features

- [Experimental] Group results by grandparent directory (256)
- This feature is favor for [Optuna](https://optuna.org/) tool, [an MNIST example](https://gist.github.com/disktnk/1675e167b2c8351393f5d290ef064ead) using with Optuna
-
<img width="500" alt="cap_grouping_example" src="https://gist.githubusercontent.com/disktnk/1675e167b2c8351393f5d290ef064ead/raw/affb40e978896372ba9e380c7a194c7038a5b05c/cap_grouping_example_w_ref.png">


Improvements

- Add checkbox next to legend (250)
- 
- Add table setting on asset page (234)
- 
- Support asset reporting called by more than one process (251)
- Support subdirectory option on asset report (249)
- Change result checkbox to eye icon (255)

New features

- Visualize image and audio data on training (197, 206, 214, 242)
- provide [`summary`](https://chainerui.readthedocs.io/en/stable/reference/module.html#asset-summaries) module to output binary and report to ChainerUI server
- see [documents](https://chainerui.readthedocs.io/en/stable/assets.html), basic usage is followed
-
<img width="1091" alt="asset_page_flow" src="https://user-images.githubusercontent.com/414255/49984543-e74eed00-ffab-11e8-9282-9957dbfd96cd.png">


Bug fixes and refactoring

- upgrade React version (222)
- fix to return None on command and snapshot ID (213)
- fix overlapping between chart tooltip and result table (225)