ZEPPELIN-41 fix: migrated to slf4j, common versions moved to parent dependencyManagement, sibling dependencies updated to use {project.version}
ZEPPELIN-37 profile for downloading hadoop 0.20.2 (test dependency) was moved to Zengine module
ZEPPELIN-41 fix: zengine module clenup: all warnings fixed
ZEPPELIN-41 fix: web module clenup
ZEPPELIN-41 fix: server module clenup
ZEPPELIN-41 fix: CLI module clenup
Wicket server-side templating engine dependecy dropped
ZEPPELIN-37: slf4j backend dependecy added
ZEPPELIN-37: log4j dependecy excluded
Create physical layer abstraction. ZEPPELIN-42