Qcommandlineparser (#199)

* Replaced getoptplusplus with QCommandLineParser. Fixes #39

* enabling C++11 if possible

* enabling C++11 if possible

* fixed gcc compilation issues

* fixed linux builds and improved os x build

* trying to fix dispmanx

* trying to fix dispmanx

* simplified travis build script

* fixed argumentparser default values

* rewrote validator system and made sure default arguments are processed correctly

* rewrote validator system and made sure default arguments are processed correctly

* fixed bool vs. regular options

* oops... removing debug code

* reverted screenshot api change

libsrc/commandline/ImageOption.cpp

@@ -0,0 +1,18 @@
+#include "commandline/ImageOption.h"
+
+using namespace commandline;
+
+bool ImageOption::validate(Parser & parser, QString & value)
+{
+    if(value.size()){
+		_image = QImage(value);
+
+		if (_image.isNull())
+		{
+			_error = QString("File %1 could not be opened as image").arg(value);
+			return false;
+		}
+    }
+
+    return true;
+}