BUG display.max_colwidth do not accept -1 for unlimited width
#### Code Sample, a copy-pastable example if possible

```python
import pandas as pd
pd.set_option("display.max_colwidth", -1)
```
#### Problem description

There is a regression with `"display.max_colwidth"`. In the past, it was only accepting integer. The way to no limit the size was to pass `-1`. In pandas 1,0, this option becomes more consistent and not limiting the width should be set with `None`. However, the support for negative integer was removed.

Thus, one would need to either set to `-1` or `None` depending on the pandas version. It would be best to support both options. Potentially, support for negative integer could be removed with a deprecation cycle.