Add an onFocusEvent method, to implement "help"

Signed-off-by: Gergely Nagy <algernon@keyboard.io>

src/kaleidoscope/FocusSerial.cpp

@@ -68,6 +68,11 @@ bool FocusSerial::handleHelp(const char *command,
   return true;
 }
 
+EventHandlerResult FocusSerial::onFocusEvent(const char *command) {
+  handleHelp(command, PSTR("help"));
+  return EventHandlerResult::OK;
+}
+
 void FocusSerial::printSpace(void) {
   Serial.print(F(" "));
 }

src/kaleidoscope/FocusSerial.h

@@ -42,6 +42,7 @@ class FocusSerial : public kaleidoscope::Plugin {
     return EventHandlerResult::OK;
   }
   EventHandlerResult beforeReportingState();
+  EventHandlerResult onFocusEvent(const char *command);
 
  private:
   static char command_[32];