ENH: options for controlling features

[jreback]

Various feature changes in the future might be invasive to the long-term support (LTS) concept. IOW, having a deprecation warning for Panel. So allow an option to control this.

• Deprecate Panel, Deprecation of Panel ? #13563
• Deprecate .ix: DEPR: deprecate .ix #14218

something like:

options.features.panel = 'warn' | 'raise' | 'ignore'
options.features.ix = 'warn' | 'raise' | 'ignore'

These would default to warn, but can then be user settable. Normally don't like changes to global state, but if you are using a 'deprecated' feature, easiest to silence things like this.

[jreback]

@jorisvandenbossche @TomAugspurger @shoyer @wesm

[shoyer]

Sure, this seems fine to me, though showing examples of how to do this with warnings.filterwarnings might be enough, e.g., warnings.filterwarnings('ignore', 'panel', FutureWarning).

[jbrockmendel]

Closeable? The motivating cases in the OP have been handled and I haven't heard any clamor for this type of switch.

[TomAugspurger]

We may want something like this to let people opt into NA integer / string dtype by default. But we can reopen at that time if necessary.