renamed the "Test" device to be "File"

No functional changes, but
- files have been renamed
- the device name is now "file" not "test"


Former-commit-id: 3fbc03c3fe1d764654c1d28ebb80562ce6276ab1

libsrc/leddevice/LedDeviceFile.cpp

@@ -0,0 +1,31 @@
+
+// Local-Hyperion includes
+#include "LedDeviceFile.h"
+
+LedDeviceFile::LedDeviceFile(const std::string& output) :
+	_ofs(output.empty()?"/home/pi/LedDevice.out":output.c_str())
+{
+	// empty
+}
+
+LedDeviceFile::~LedDeviceFile()
+{
+	// empty
+}
+
+int LedDeviceFile::write(const std::vector<ColorRgb> & ledValues)
+{
+	_ofs << "[";
+	for (const ColorRgb& color : ledValues)
+	{
+		_ofs << color;
+	}
+	_ofs << "]" << std::endl;
+
+	return 0;
+}
+
+int LedDeviceFile::switchOff()
+{
+	return 0;
+}