Switch between Build Configurations (release and debug) with a new project configuration option build_type // Resolve #2184

platformio/project/options.py

@@ -111,6 +111,8 @@ ProjectOptions = OrderedDict([
                         buildenvvar="BOARD_FLASH_MODE"),
 
         # Build
+        ConfigEnvOption(name="build_type",
+                        type=click.Choice(["release", "debug"])),
         ConfigEnvOption(name="build_flags",
                         multiple=True,
                         sysenvvar="PLATFORMIO_BUILD_FLAGS",