Added argument to autocorrelation_plot
Added additional parameter to autocorrelation_plot to plot the specified number of lags in case of long time series.

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21301?src=pr&el=h1) Report
> Merging [#21301](https://codecov.io/gh/pandas-dev/pandas/pull/21301?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/4274b840e64374a39a0285c2174968588753ec35?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `25%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/21301/graphs/tree.svg?width=650&height=150&src=pr&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/21301?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #21301      +/-   ##
==========================================
- Coverage   91.85%   91.84%   -0.01%     
==========================================
  Files         153      153              
  Lines       49546    49548       +2     
==========================================
  Hits        45509    45509              
- Misses       4037     4039       +2
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.24% <25%> (-0.01%)` | :arrow_down: |
| #single | `41.87% <25%> (-0.01%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/21301?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/plotting/\_misc.py](https://codecov.io/gh/pandas-dev/pandas/pull/21301/diff?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19taXNjLnB5) | `38.7% <25%> (-0.28%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21301?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/21301?src=pr&el=footer). Last update [4274b84...3a6cacb](https://codecov.io/gh/pandas-dev/pandas/pull/21301?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
