Ref T259, Ref T243 remove aircraft parts and situations from interpolator

* no longer using the add parts/situations signals
* will use the remote aircraft provider parts directly

Result: all parts/situations are stored only once in memory and in one single place

src/blackcore/context/contextnetworkimpl.cpp

@@ -114,6 +114,12 @@ namespace BlackCore
             return m_airspace->remoteAircraftParts(callsign, cutoffTimeBefore);
         }
 
+        int CContextNetwork::remoteAircraftPartsCount(const CCallsign &callsign, qint64 cutoffTimeBefore) const
+        {
+            Q_ASSERT(m_airspace);
+            return m_airspace->remoteAircraftPartsCount(callsign, cutoffTimeBefore);
+        }
+
         int CContextNetwork::remoteAircraftSituationsCount(const CCallsign &callsign) const
         {
             Q_ASSERT(m_airspace);