Breaking changes

Consolidate classes naming to match the convention with @material-ui/core

We are changed all of our internal components to use:

1. Unique component name and display name in component namespace
2. All internal components of pickers are named with prefix MuiPickers from now
3. Every component have style option called root which points to the root
4. Using pseudo-classes (e.g. .Mui-disabled) to improve the overriding experience

MuiPickersDay: {
  &$disabled:{ 
     // provide any disabled styles
  }
}

Avoid localized time formats

In order to get rid of unexpected falling back to the unmasked input and warnings – we must avoid usage of localized time format (e.g. "p") and use predefined formats. We do have support for it via date-io and simply use hh:mm for 24h clock and hh:mm a for 12h.

Fixes / enhancements 🐛

• [DatePicker] Don't run onChange if same date selected (#1967) @tdranv
• [Calendar] Fix not rerendering days when reduceAnimations provided (#1994)
• [docs] Update examples formatting to match main v2 (#1977)