Reduce the amount of supported OneShot layers

Instead of supporting up to 24 one-shot layers, support only 8. This
allows us to fit all state in 16 bits, down from 32, saving us almost
200 bytes of program memory.

Partially addresses #8.

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

src/Kaleidoscope/OneShot.cpp

@@ -26,9 +26,9 @@ namespace KaleidoscopePlugins {
   uint32_t OneShot::startTime = 0;
   uint16_t OneShot::timeOut = 2500;
   uint16_t OneShot::holdTimeOut = 250;
-  uint32_t OneShot::State = 0;
+  uint16_t OneShot::State = 0;
-  uint32_t OneShot::stickyState = 0;
+  uint16_t OneShot::stickyState = 0;
-  uint32_t OneShot::pressedState = 0;
+  uint16_t OneShot::pressedState = 0;
   uint32_t OneShot::leftMask;
   uint32_t OneShot::rightMask;
   Key OneShot::prevKey;

src/Kaleidoscope/OneShot.h

@@ -43,9 +43,9 @@ namespace KaleidoscopePlugins {
 
   private:
     static uint32_t startTime;
-    static uint32_t State;
+    static uint16_t State;
-    static uint32_t stickyState;
+    static uint16_t stickyState;
-    static uint32_t pressedState;
+    static uint16_t pressedState;
     static uint32_t leftMask;
     static uint32_t rightMask;
     static Key prevKey;