sprinter.js
function deduplicateCollaborators(collaborators) {
    var foundLogins = [];
    return _.filter(collaborators, function (collaborator) {
        var duplicate = false
          , login = collaborator.login;
        if (foundLogins.indexOf(login) > -1) {
            duplicate = true;
        } else {
            foundLogins.push(login);
        }
        return ! duplicate;
    });
}
function deduplicateCollaborators(collaborators) {
    var foundLogins = [];
    return _.filter(collaborators, function (collaborator) {
        var duplicate = false
          , login = collaborator.login;
        if (foundLogins.indexOf(login) > -1) {
            duplicate = true;
        } else {
            foundLogins.push(login);
        }
        return ! duplicate;
    });
}
Removes duplicate collaborators.
@param collaborators
@returns {Array}