Add method to allow upload of keymap for individual layer

src/Kaleidoscope/EEPROM-Keymap-Focus.h

@@ -23,5 +23,8 @@
 
 #define FOCUS_HOOK_KEYMAP FOCUS_HOOK(EEPROMKeymap.focusKeymap, "keymap.map")
 
+#define FOCUS_HOOK_KEYMAP_LAYER FOCUS_HOOK(EEPROMKeymap.focusKeymapLayer, \
+                                           "keymap.layer")
+
 #define FOCUS_HOOK_KEYMAP_TRANSFER FOCUS_HOOK(EEPROMKeymap.focusKeymapTransfer, \
                                               "keymap.transfer")

src/Kaleidoscope/EEPROM-Keymap.cpp

@@ -107,6 +107,22 @@ bool EEPROMKeymap::focusKeymap(const char *command) {
   return true;
 }
 
+bool EEPROMKeymap::focusKeymapLayer(const char *command) {
+  if (strcmp_P(command, PSTR("keymap.layer")) != 0) {
+    return false;
+  }
+
+  uint8_t layer = Serial.parseInt();
+  uint16_t keysPerLayer = ROWS * COLS;
+  uint16_t offset = layer * keysPerLayer;
+  for (uint16_t k = 0; (k < keysPerLayer) && (Serial.peek() != '\n'); k++) {
+    updateKey(layer + k, parseKey());
+  }
+
+  return true;
+
+}
+
 bool EEPROMKeymap::focusKeymapTransfer(const char *command) {
   if (strcmp_P(command, PSTR("keymap.transfer")) != 0)
     return false;

src/Kaleidoscope/EEPROM-Keymap.h

@@ -36,6 +36,7 @@ class EEPROMKeymap : public KaleidoscopePlugin {
   static Key getKeyOverride(uint8_t layer, byte row, byte col);
 
   static bool focusKeymap(const char *command);
+  static bool focusKeymapLayer(const char *command);
   static bool focusKeymapTransfer(const char *command);
 
   static void updateKey(uint16_t base_pos, Key key);