[Simulator] Further improvements (reload radio, momentary switches, etc.) (#4303)

* [Simulator] Add ability to reload all radio data w/out exiting simulator (will also adjust UI for any hardware changes); Refactor how keymap help text is generated.

* [Simulator] Only update channel/logical switch/GVar output displays if the corresponding tab is actually visible (further CPU usage reductions).

* [Simulator] Implement momentary toggle switches with "latch" function.

* [Simulator] Mouse wheel event over multi-position knobs now properly rotates them to detent positions.

* [Simulator] Fix mouse wheel event propagation after multi-position knob rotation; Cosmetics.

* [Simulator] Internals: Greatly improve object cleanup on exit; Refactor SimulatedUIWidget timer event triggering.

* [Simulator] Fix throttle stick position/lock not being set properly upon repeated launches from Companion.

* [Simulator] Fix build w/out SDL. KnobWidget cleanup.

* [Companion] Do NOT delete SimulatorInterface on simulator dialog exit (fix possible crash on dialog close).

* [Simulator] Ensure joystick is NULL at start.

* [Simulator] Fix/improve color blending on 4-bit screens with different BG colors; Cosmetics.

* [Simulator] Fix LCD screenshot folder path; Fix timer slot for Qt backwards compatibility.

* [TravisCI] Set Qt version to 5.3 to match release build servers.

* Fixed segfault when saving setup with no models defined [Horus]

* Fixed radio data import [Horus] (broken in 0f90ff0b65)

* [Simulator] Always keep toggle switch active while held with mouse button.

companion/src/simulation/simulateduiwidget.cpp

@@ -83,8 +83,9 @@ QPolygon SimulatedUIWidget::polyArc(int ctrX, int ctrY, int radius, int startAng
   return polygon;
 }
 
-void SimulatedUIWidget::timedUpdate(unsigned loop)
+void SimulatedUIWidget::updateUi()
 {
+  //static quint32 loop = 0;
   if (m_lcd->isVisible()) {
     bool lightEnable;
     if (m_simulator->lcdChanged(lightEnable)) {
@@ -126,7 +127,7 @@ void SimulatedUIWidget::saveScreenshot(int idx)
       m_simuDialog->traceCallback("SIMULATOR ERROR - Cannot open screenshot folder, check your settings.\n");
       return;
     }
-    fileName += QString("%1screenshot_%2.png").arg(dir.absolutePath(), QDateTime::currentDateTime().toString("yy-MM-dd_HH-mm-ss"));
+    fileName += QString("%1/screenshot_%2.png").arg(dir.absolutePath(), QDateTime::currentDateTime().toString("yy-MM-dd_HH-mm-ss"));
   }
   m_lcd->makeScreenshot(fileName);
 }