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/power/battery_test_app/battery_test_app.c

@@ -1,6 +1,6 @@
 #include "battery_test_app.h"
 
-#include <notification/notification-messages.h>
+#include <notification/notification_messages.h>
 
 void battery_test_dialog_callback(DialogExResult result, void* context) {
     furi_assert(context);

applications/power/power_cli.c

@@ -2,7 +2,7 @@
 
 #include <power/power_service/power.h>
 #include <cli/cli.h>
-#include <furi-hal.h>
+#include <furi_hal.h>
 
 void power_cli_poweroff(Cli* cli, string_t args, void* context) {
     Power* power = furi_record_open("power");

applications/power/power_service/power.c

@@ -2,7 +2,7 @@
 #include "views/power_off.h"
 
 #include <furi.h>
-#include <furi-hal.h>
+#include <furi_hal.h>
 #include <gui/view_port.h>
 #include <gui/view.h>
 

applications/power/power_service/power_api.c

@@ -1,8 +1,8 @@
 #include "power_i.h"
 
 #include <furi.h>
-#include "furi-hal-power.h"
-#include "furi-hal-bootloader.h"
+#include "furi_hal_power.h"
+#include "furi_hal_bootloader.h"
 
 void power_off(Power* power) {
     furi_hal_power_off();

applications/power/power_service/power_i.h

@@ -9,7 +9,7 @@
 #include <gui/modules/popup.h>
 #include "views/power_off.h"
 
-#include <notification/notification-messages.h>
+#include <notification/notification_messages.h>
 
 #define POWER_BATTERY_HEALTHY_LEVEL 70