COOPR-624: Added dependency to slf4j-nop for correct bindings.

@wolf31o2 Dependency to slf4j-nop has been added for correct bindings, as mentioned in the https://issues.cask.co/browse/COOPR-624?focusedCommentId=12310&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-12310

Please take a look.