* new slot syntax in ATC station component
* formatting, comments
* tab order
* utility function for severity in status message
* null checks in threadutils
* invalidKey function in datastore
* changed data object keys (cached objets)
* added missing value object compare cases
* renamed timer in context network
* finder function for model list
* renamed getContainer to container (as it is just a reference)
* consolidated ICoordinateGeodetic (e.g. fixed nested properties)
* shifted common functionality for objects/containers with callsign into interface
* shifted common functionality for objects/containers with geo position into interface
* shifted common functionality for objects/containers with timestamp into interface
* updated corresponding value objects / specialized lists
* adjusted all places where renamed functions are used
* Specialized formatters (e.g. for bool, for PQs etc.) allow specialized look and feel for each column
* Fixed isValidComFrequency used for formatters
* Changed models to use formatters
* Outdated propertyByIndexAsString methods removed
* During the above tasks: fixed override keyword in some places
* Column tooltips
* refs #323, wrong column name fix