Addendum to #392

Minor bug that broke the grid
Add local phaidra development resources
Use phaidra in staging3
Simplify retriever get communication in state
Fix paths to arethusa-server
Extract Doc class to arethusaClasses
Use locator instead of $location
Switch order of injectables of TreebankRetriever
Fix get in review
Start to refactor TreebankRetriever
Rename commonRetriever to retrieverHelper
Extract preselection handling to a helper
Extract sentence creation to arethusaClasses
Extract Token object from treebankRetriever
Implement first quick run of parsing phaidra tbs
Allow postag or attrs from retriever in morph
Minor formatting
Use greek as base in staging3
Minor refactor in morph
More dev resources