Rename CApplication member function to be better readable

The combination of the method's name 'signalStartupAutomatically'
and the default argument, I completely misunderstood the purpose
of the method in case the argument was skipped.
'a.signalStartupAutomatically()' actually disabled automatic signaling.

src/blackcore/application.h

@@ -168,7 +168,7 @@ namespace BlackCore
         bool isRunningInDeveloperEnvironment() const { return this->m_devEnv; }
 
         //! Signal startup automatically or individually
-        void signalStartupAutomatically(bool signal = false);
+        void setSignalStartupAutomatically(bool enabled);
 
         //! Info string
         QString getEnvironmentInfoString(const QString &separator) const;