As a plugin developer you can use this plugin as dependency of your plugin by adding a dependency tag to your POM.
To add the latest version of this plugin as a maven dependency, use the following:
<dependency>
<groupId>net.hurstfrost.jenkins</groupId>
<artifactId>avatar</artifactId>
<version>28.v2e722a_1e67ea_</version>
</dependency>