Changes for Issue #245
Created by: StephanMa
A lot of Changes for Issue #245 (closed) Togehter with #266 . #274 and some Bug-Fixing
-- When just 1 Charter was imported inside a Fond/Collection, Function next-and-previous fails. Check for additional Charters was fixed. If there isn't another charter, wcharter:next gets a reference to wcharter:previous (itself)