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

applications/gpio/views/gpio_usb_uart.c

@@ -1,6 +1,6 @@
 #include "../usb_uart_bridge.h"
 #include "../gpio_app_i.h"
-#include "furi-hal.h"
+#include "furi_hal.h"
 #include <gui/elements.h>
 
 struct GpioUsbUart {