Teach plugin to print out the contents of a given layer

src/Kaleidoscope/EEPROM-Keymap.cpp

@@ -115,9 +115,19 @@ bool EEPROMKeymap::focusKeymapLayer(const char *command) {
   uint8_t layer = Serial.parseInt();
   uint16_t keysPerLayer = ROWS * COLS;
   uint16_t offset = layer * keysPerLayer;
+  if (Serial.peek() == '\n') {
+    for (uint8_t row = 0; row < ROWS; row++) {
+      for (uint8_t col = 0; col < COLS; col++) {
+        Key k = Layer.getKey(layer, row, col);
+        printKey(k);
+        ::Focus.printSpace();
+      }
+    }
+  } else {
     for (uint16_t k = 0; (k < keysPerLayer) && (Serial.peek() != '\n'); k++) {
       updateKey(layer + k, parseKey());
     }
+  }
 
   return true;