SOLUTION
1) Add the dependency of the artifact jclouds-slf4j (http://mvnrepository.com/artifact/org.jclouds.driver/jclouds-slf4j/1.5.4)
<dependency>
<groupId>org.jclouds.driver</groupId>
<artifactId>jclouds-slf4j</artifactId>
<version>1.5.4</version>
</dependency>
2) Rebuild the project
The pom.xml may look like this:
...
<dependencies>
<dependency>
<groupId>org.jclouds</groupId>
<artifactId>jclouds-allcompute</artifactId>
<version>1.5.7</version>
</dependency>
<dependency>
<groupId>org.jclouds</groupId>
<artifactId>jclouds-allblobstore</artifactId>
<version>1.5.7</version>
</dependency>
<dependency>
<groupId>org.jclouds.driver</groupId>
<artifactId>jclouds-slf4j</artifactId>
<version>1.5.4</version>
</dependency>
</dependencies>
...