Naming and coding style convention, new linter tool. (#945)

* Makefile, Scripts: new linter
* About: remove ID from IC
* Firmware: remove double define for DIVC/DIVR
* Scripts: check folder names too. Docker: replace syntax check with make lint.
* Reformat Sources and Migrate to new file naming convention
* Docker: symlink clang-format-12 to clang-format
* Add coding style guide

firmware/targets/f6/ble_glue/ble_app.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdbool.h>
+#include <stdint.h>
+
+bool ble_app_init();
+void ble_app_get_key_storage_buff(uint8_t** addr, uint16_t* size);
+void ble_app_thread_stop();
+
+#ifdef __cplusplus
+}
+#endif