Added referers file:
 - Includes new social: sub-section adapted from:

https://github.com/piwik/piwik/blob/master/core/DataFiles/Socials.php

 - Moved all search engines into a search: sub-section
Updated to start referencing social
Updated to include some (initial email providers)
Simplified the interface and added in the idea of medium (Enum in Java and Enumeration in Scala)
Updated referers.yml and referers.json in sub-folders following updates to master copy
Moving to referers files
Removed historic search.yml files
Compiles again with all features added.

Next need to write some more vigorous tests using DataTables
Version bump
Simplified the JMedium -> Medium conversion
Renamed confusing args
Some small improvements
Fixed internal referers
Update referers.yml
Updated referers.yml and referers.json in sub-folders following updates to master copy
Updated referers.yml and referers.json in sub-folders following updates to master copy
Updated referers.yml and referers.json in sub-folders following updates to master copy
Updated referers.yml and referers.json in sub-folders following updates to master copy
Updated referers.yml and referers.json in sub-folders following updates to master copy
Updated referers.yml and referers.json in sub-folders following updates to master copy