<users type="array">
	<user>
		<id>1</id>
		<login>user</login>
		<firstname>Alex</firstname>
		<lastname>Black</lastname>
		<mail>anton@ahausoftware.com</mail>
		<created_on>2015-03-18T00:08:44Z</created_on>
		<last_login_on>2016-03-31T15:18:41Z</last_login_on>
		<avatar_url>https://www.gravatar.com/avatar/f1f7086b63fa35b7588614516fade808?rating=PG&size=50&default=monsterid</avatar_url>
	</user>
</users>

login - display only for admin or if the user is current
mail	- display only for admin or if the user swith off 'Hide my email address' in Preferences
avatar_url - display if option 'Use Gravatar user icons' is enabled in Settings

<settings>
    <text_formatting>textile</text_formatting>
    <gravatar_enabled>false</gravatar_enabled>
    <gravatar_default>wavatar</gravatar_default>
    <version>Redmine 3.1.1.stable</version>
    <environment></environment>
</settings>

<settings>
	<rest_api_enabled>true</rest_api_enabled>
	<plugin_version>0.0.6</plugin_version>
</settings>

  $ cd /path/to/redmine/plugins
  $ git clone git://github.com/ANovitsky/redmine_shared_api.git redmine_shared_api