Zoom and pan in GUI

Support zooming in or out the image and panning. This is to help inspecting pixel details

applications/gui/src/screen.cpp

@@ -382,7 +382,6 @@ bool ftl::gui::Screen::mouseMotionEvent(const Eigen::Vector2i &p, const Eigen::V
 		return true;
 	} else {
 		if (camera_) {
-			LOG(INFO) << "BUTTON = " << button << ", MOD = " << modifiers;
 			if (button == 1) {
 				camera_->mouseMovement(rel[0], rel[1], button);
 			} else if (button == 2) {