* new constructor in column class
* removed overridden data method, no longer needed
* added icons for ATC station views
* QPixmap comparison for such columns (free functions)
* changed return type for updateFromVatsimDataFileStation
* improved resolution for own aircraft
* convenience method findFirstByCallsign
* automatically convert frequency to MHz for ATC station
* improved output in toQString
* GUI, flight plan formatting
* corrected logging for network context
* override keyword in listmodelbase
Deals with a special topic: While frequencies at VATSIM/flightsim are usually set in 25kHz spacing, some ATC stations (radar) require 8.33kHz tuning.
The now made extension handles this and allows to listen to a voice room even if the corresponding frequency is not exactly tuned in.
Example: EKDK_CTR 135,270 but needs to be tuned in as 135,275
The new compare is implemented using "multimethods" described in the book Advanced C++ Programming Styles and Idioms by James Coplien.
First, the isA method is used to determine which of the values being compared is the most general. (For example, CLength is more general than CAltitude.)
Then the compareImpl method is called on the most general value, with the other value as an argument.
If there is not a direct inheritance relation between the two values (or they are the same class) then the comparison is invalid and a assert is triggered.
* rename CStatusMessages to CStatusMessageList
* rename NetworkVatlib to CNetworkVatlib
* replace all occurrences of Realname with RealName (correct camel case)
* CSequence method corresponding to CList::append is push_back
* don't compile the qdbuscpp2xml metadata plugin by default
* CAircraftIcao string members always trimmed and capitalized
* added CComSystem::roundTo25KHz
* using epsilon comparison in a couple of places
refs #81
