Tqdm

- propagate and `close()` on exceptions (926 <- 548)
- fix nested `clear()`
- rework nested `close()` (930 <- 924 <- 918, 677)
+ reduces screen flicker/blank space at the cost of ordering
- update all documentation & demos
- add and update tests
- dev framework: add pre-commit helper

- fix `_utils` `ImportError` => `DeprecationWarning` (928 <- 927)

- add automatic `nrows` and expose for manual override (918 -> 924)
- expose and warn about small `chunksize` in `tqdm.contrib.concurrent.process_map` (912)
- fix py2 file stream comparison (727 -> 730)
- deprecate `utils._environ_cols_wrapper`
- add and update tests
- add documentation

- fix `notebook` exceptions (669 <- 650)
+ `set_description()` when `disable=True`
- `contrib.concurrent`: avoid unnecessary `len(iterable)` (893)
- update documentation
+ clarify etymology (895)
+ fix minor typo (890)
+ update contributors and years
- update tests
- fix CI tests for PRs

- support `pandas==1.0.0` (780, 555)
- minor metadata updates
- minor CI test update

- `notebook`: update `disable=None` behaviour (880)
- `tqdm.keras`: support `tensorflow.keras` as well as `keras` (885)
- add `contrib` (882)
+ `tenumerate` (840 <- 480, 402)
+ `tzip` <= `zip`
+ `tmap` <= `map`
+ add `concurrent` module
* `thread_map` <= `concurrent.futures.ThreadPoolExecutor.map`
* `process_map` <= `concurrent.futures.ProcessPoolExecutor.map`
+ add `itertools` module (225) stub
* `product`
- add & update tests
- add & update documentation
+ [README](https://github.com/tqdm/tqdm#tqdm)
+ [examples/](https://github.com/tqdm/tqdm/tree/master/examples)
- update CI framework