Fix the isModifier helper macro

The macro needs to check `.keyCode` and `.flags` separately, due to byte
ordering. If it does not, it will easily catch other things.

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>

src/Akela/OneShot.cpp

@@ -35,7 +35,7 @@ namespace Akela {
   // --- helper macros ------
 
 #define isOS(key) (key.raw >= OS_FIRST && key.raw <= OS_LAST)
-#define isModifier(key) (key.raw >= Key_LCtrl.raw && key.raw <= Key_RGUI.raw)
+#define isModifier(key) (key.keyCode >= Key_LCtrl.raw && key.keyCode <= Key_RGUI.raw && key.flags == 0)
 #define isLayerKey(key) (key.flags & (KEY_FLAGS | SYNTHETIC | SWITCH_TO_KEYMAP) && key.keyCode >= MOMENTARY_OFFSET && key.keyCode <= MOMENTARY_OFFSET + 23)
 
 #define isOneShot(idx) (bitRead (State, idx))