Added new CxxPreProcessorCache class to boost performance
Added new CxxPreProcessorScannerBase which collects only include files
Removed try/catch block (not needed)
Renamed CxxPreProcessorScannerBase -> CxxPreProcessorIncludeStatementCollector (long name...)
Added 2 new classes: CIncludeStatementCollector, CxxUsingNamespaceCollector
Fixed: Random crash when 'Scan for all using namespace statements' option is enabled