[MaterialDatePicker] Choose different Calendar API and define custom DateTime Format

Nobody has claimed this yet.

**Is your feature request related to a problem? Please describe.**
The current issue is that `MaterialDatePicker` is using `java.util.Calendar` (Java 7) as an underlying API to get UTC epoch millisecond and datetime format, and convert it to [`Month`](https://github.com/material-components/material-components-android/blob/master/lib/java/com/google/android/material/datepicker/Month.java) object where `year` property is retrieved from `Calendar.get(Calendar.YEAR)`. This causes date string to always show year in Christian Era and/or B.C.E. As a Thai user, most of Thai are familiar with Buddhist Calendar (Buddhist year = Christian year + 543 e.g. 2021 = 2564), so elder users tend to not know which Christian year of their birthdate.

**Describe the solution you'd like**
- It would be great if we can customize or delegate how `Month` object is created, so it does not limit to only `java.util.Calendar` API, but open to `java.time.chrono.ThaiBuddhistDate` or `org.threeten.bp.chrono.ThaiBuddhistDate` (Threeten ABP).
```Kotlin
MaterialDatePicker.Builder
.datePicker()
.setCustomMonth(CustomMonth())
```
```Kotlin
open class CustomMonth(private val thaiBuddhistDate: ThaiBuddhistDate) : Month() {

override fun getYear(): Int {
return thaiBuddhistDate.getLong(ChronoField.YEAR).toInt()
}
}
```
- Moreover, a custom date format should be a feature of `MaterialDatePicker` as well.

**Additional context**
Example screenshots from another library ([ThaiDateTimePicker](https://github.com/layerlre/ThaiDateTimePicker) - **very old library**)

Start with lib/java/com/google/android/material/datepicker/Month.java and the MaterialDatePicker entry point to understand how Calendar supplies the year and formatting data. Compare the requested custom chronology and date-format support with the existing API boundaries. Done would require an agreed design and corresponding support for non-Gregorian years and custom formatting.

Written by the indexing model from the issue text.