Feature request: getBaladyiatsForDaira

[Fcmam5]

Implement a new feature that takes a daira name (either in French, English or Arabic) and returns either a list of baladyiats or null.

• getBaladyiatsForDaira(name: string): string

Please, don't forget to update the documentation in the README file (check this example PR).

[oussamabouchikhi]

@Fcmam5 please assign me to this