[DatePicker] Auto switch the view when a year is selected

[donratta]

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This is in relation to issue #4949 (comment) where it is not intuitive to the user to click the date after selecting the year. I added a new attribute autoSwitch; where if set true changes the view back to the monthDay view where the user can now complete the date selection.

<MaterialDatePicker hintText={this.props.hintText || 'Click to select a date'}
                            hintStyle={this.props.hintStyle || styles.hint}
                            autoSwitch={true}
                            autoOk={true}/>

[oliviertassinari]

it is not intuitive to the user to click the date after selecting the year.

I definitely agree. The Calendar app of Google on Android is behaving like autoSwitch={true}.
It's a much better UX.

I don't think that we need to expose this new property. What about simply implementing the behavior?

[donratta]

@oliviertassinari I agree also. Just wanted to provide the extra flexibility; I have edited the PR to do this implicitly now. Awesome library btw!

[oliviertassinari]

Thanks