Fix inverted parameters

This commit relates to issue #8, and fixes exactly the same kind of bug.
[fix] Authors are identified by their username and not by their id
Merge pull request #9 from tdurieux/fix

[fix] Authors are identified by their username and not by their id
[new #11] Add API to retrieve user list

An authenticated user may retrieve the list of users. This list can be
filtered using the parameter `name` which filters out users that do not
start with the given value

close #11