Add command line parameters. Fixes #30 (#89)

* Add command line parameters. Fixes #30

* Fixed compile errors

* Fixed code review findings

* Fixed code review findings, take 2

app/settings/streamingpreferences.cpp

@@ -22,7 +22,8 @@
 #define SER_MDNS "mdns"
 #define SER_MOUSEACCELERATION "mouseacceleration"
 
-StreamingPreferences::StreamingPreferences()
+StreamingPreferences::StreamingPreferences(QObject *parent)
+    : QObject(parent)
 {
     reload();
 }

app/settings/streamingpreferences.h

@@ -8,7 +8,7 @@ class StreamingPreferences : public QObject
     Q_OBJECT
 
 public:
-    StreamingPreferences();
+    StreamingPreferences(QObject *parent = nullptr);
 
     Q_INVOKABLE static int
     getDefaultBitrate(int width, int height, int fps);