rollback to c++11 to save on flash

platformio.ini

@@ -16,10 +16,10 @@ core_build_flags =
   -D NDEBUG
   -D ARDUINO_ARCH_ESP32=1
   -D ESP32=1
-  -std=gnu++17 -Os
+  ; -Os
 
-core_unbuild_flags = -std=gnu++11 
-; core_unbuild_flags = 
+; core_unbuild_flags = -std=gnu++11 
+core_unbuild_flags = 
 
 ; my_build_flags is set in pio_local.ini
 my_build_flags =
@@ -68,8 +68,6 @@ extra_scripts =
   scripts/rename_fw.py
 board = esp32dev
 platform = espressif32
-; platform_packages =
-; 	framework-arduinoespressif32@3.20005.220925
 board_upload.flash_size = 4MB
 board_build.partitions = esp32_partition_4M.csv
 build_flags = ${common.build_flags}