DOC: removed vendored IPython.sphinxext - take 2
This reverts commit d6049a0efb7c04996bc374f3747bab8fe4c84bac.

xref https://github.com/pandas-dev/pandas/issues/18147, re-do  https://github.com/pandas-dev/pandas/pull/18193 (which was reverted in https://github.com/pandas-dev/pandas/pull/18320 because there was still a bug in IPython, which is now fixed in the released version: https://github.com/ipython/ipython/pull/10907)



@TomAugspurger We were actually a bit fast, the fix of https://github.com/ipython/ipython/pull/10907 is actually not yet in a released version. # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19657?src=pr&el=h1) Report
> Merging [#19657](https://codecov.io/gh/pandas-dev/pandas/pull/19657?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/2431641ad7882326d3d65a35319ef4093cdbae9c?src=pr&el=desc) will **decrease** coverage by `0.02%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/19657/graphs/tree.svg?width=650&src=pr&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/19657?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #19657      +/-   ##
==========================================
- Coverage   91.84%   91.81%   -0.03%     
==========================================
  Files         153      153              
  Lines       49265    49265              
==========================================
- Hits        45245    45235      -10     
- Misses       4020     4030      +10
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.2% <ø> (-0.03%)` | :arrow_down: |
| #single | `41.9% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/19657?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/19657/diff?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19jb252ZXJ0ZXIucHk=) | `65.07% <0%> (-1.74%)` | :arrow_down: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/19657/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `84.73% <0%> (+0.2%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19657?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/19657?src=pr&el=footer). Last update [2431641...8ec7f4b](https://codecov.io/gh/pandas-dev/pandas/pull/19657?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Oh, I thought the backported in
https://github.com/ipython/ipython/pull/10908 was released, but apparently
not yet.

On Mon, Feb 12, 2018 at 12:33 PM, Joris Van den Bossche <
notifications@github.com> wrote:

> @TomAugspurger <https://github.com/tomaugspurger> We were actually a bit
> fast, the fix of ipython/ipython#10907
> <https://github.com/ipython/ipython/pull/10907> is actually not yet in a
> released version.
>
> —
> You are receiving this because you were mentioned.
> Reply to this email directly, view it on GitHub
> <https://github.com/pandas-dev/pandas/pull/19657#issuecomment-365017676>,
> or mute the thread
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> .
>
 this looks fine. @jorisvandenbossche merge when ready. Don't merge, we need to wait until the next IPython release .. status @jorisvandenbossche ? This needs to wait until IPython has a new release. If you rather close the PR until then, that's fine for me as well (having it open is a reminder for me, but can also open an issue) it’s fine -  IPython has released, update the PR, and this seems to be working now