* Added new classes with behavior from MetadataManager & MetadataSource
* Replaced MetadataManager usages with new classes
* New PrefixDataIOHandler which packs data into a jar
* Added mockito-core jar to lib folder
* Added mockito-all jar to lib folder and updated tests to not use junit4 annotations
* Fixed prefix generation entry points
* Specific exception for missing metadata cases
* Small change in checking missing metadata cases