Add file-like object to docs for Feather
State: closed

`read_feather` and `to_feather` accept file-like object. For example, something like this works:
```
# python -uc "import pandas, sys; print(pandas.read_feather(sys.stdin))" < a.feather 
    id
0  1.0
1  2.0
2  3.0
3  NaN
4  5.0
5  6.0
6  7.0
7  8.0
# python -uc "import pandas, sys; pandas.to_feather(pandas.read_feather(sys.stdin), sys.stdout)" < a.feather > b.feather
```

- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry


Labels:
name: Docs
name: IO Data
description: IO issues that don't fit into a more specific label

Comments:
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=h1) Report
> Merging [#17492](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/42ed4f143f8b0b386c90df9fa8a55d0f2e5a857c?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17492/graphs/tree.svg?width=650&height=150&token=eZ4WkYLtcO&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #17492      +/-   ##
==========================================
- Coverage   91.15%   91.13%   -0.02%     
==========================================
  Files         163      163              
  Lines       49534    49534              
==========================================
- Hits        45153    45144       -9     
- Misses       4381     4390       +9
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.92% <ø> (ø)` | :arrow_up: |
| #single | `40.22% <ø> (-0.07%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/feather\_format.py](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree#diff-cGFuZGFzL2lvL2ZlYXRoZXJfZm9ybWF0LnB5) | `85.71% <ø> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.72% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=footer). Last update [42ed4f1...9d6dbf0](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=h1) Report
> Merging [#17492](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/42ed4f143f8b0b386c90df9fa8a55d0f2e5a857c?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17492/graphs/tree.svg?height=150&src=pr&width=650&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #17492      +/-   ##
==========================================
- Coverage   91.15%   91.13%   -0.02%     
==========================================
  Files         163      163              
  Lines       49534    49534              
==========================================
- Hits        45153    45144       -9     
- Misses       4381     4390       +9
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.92% <ø> (ø)` | :arrow_up: |
| #single | `40.22% <ø> (-0.07%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/feather\_format.py](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree#diff-cGFuZGFzL2lvL2ZlYXRoZXJfZm9ybWF0LnB5) | `85.71% <ø> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.72% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=footer). Last update [42ed4f1...9d6dbf0](https://codecov.io/gh/pandas-dev/pandas/pull/17492?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).

thanks