Fixed name conflict

The TimerClass had a local `SpeedFaktor` variable, which is used by the sync function.
This leads to a desync between the local and the global variable and can cause the game
speed to be calculated wrong.

Example:
The game speeds up when it runs with a low framerate (the speed factor is changed
to have more accurate calculations, but the sync function still uses the "old" variable)
This can be easily repuduced by starting the game in debug mode and typing
```
maxfps 10
```
in the console to limit the framerate.

Hurrican/src/Timer.hpp

@@ -26,6 +26,9 @@
 // Klassen Deklaration
 // --------------------------------------------------------------------------------------
 
+// The Timer class needs the global SpeedFactor variable
+extern float SpeedFaktor;
+
 class TimerClass {
   private:
     std::int64_t vergangeneFrames;  // Vergangene Frames seit Beginn (für Schnitt)
@@ -40,7 +43,6 @@ class TimerClass {
     double vergangeneZeit;     // Zeit seit dem vorherigen Frame
     double aktuelleFramerate;  // Aktuelle Framerate
     int maxFPS;                // Maximum Framerate (Framebremse)
-    float SpeedFaktor;         // Faktor, mit dem alle Werte verrechnet werden
 
   public:
     TimerClass();                   // Konstruktor
@@ -69,7 +71,6 @@ class TimerClass {
 // Externals
 // --------------------------------------------------------------------------------------
 
-extern float SpeedFaktor;
 extern TimerClass Timer;
 
 #endif