New GET /people API 

This new API allows to query the emebedded database against the users
data.
It accepts query criteria, filters, sort criteria and pagination.
For example if a user make a call to know all users who have a username
that starts with "ros" and and that it is 5 characters long and
order them by sign up date descending:

GET /people?where=user.name like "ros%" and user.name.length() = 5&orderBy=user.signUpDate asc

Note: depending by the tool you use to make the call, you could escape the '%' character

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DEPRECATED APIs

APIs /user/:username and /user/:username/exists are deprecated
To obtain the same result of
GET /user/:username
you have to to:
GET /people?where=user.name="username"