Implement bootloader #137 (#142)

* Boot: switch to DFU routines. Implements #132 part 1 of 2.

* Boot: boot to DFU shortcut, hard reset USB on each boot. Implements #132 part 2 of 2.

* Deploy scripts: fix path for deploy dfu.

* Bootloader: initial version. Target_f2: rebase, update deployment scripts.

* Bootloader: cleanup, refactor switch2 proc. Readme,wiki: document bootloader.

* Wiki: deploy symlinks as files, bootloader info.

* Target_f2: valid flash size in linker script.

* Github CI: bootloader build and artifacts.

* Bootloader: rename platforms to targets.

* Bootloader: change dfu/os colors.

* disable set -e

* lint code

* add bootloader testing page

Co-authored-by: Aleksandr Kutuzov <aku@plooks.com>
Co-authored-by: aanper <mail@s3f.ru>

wiki/fw/Firmware.md

@@ -6,30 +6,31 @@ _Overview of Flipper firmware architecture:_
 
 ```
 .
-├── applications 	# Flipper applications
-│   └── furi_test	# Test app for checking and demonstrating FURI func
-├── core 	# Main feature like OS, HAL (target-independed)
-├── target_f1 # Target-depended code for target F1
-│   ├── Drivers # STM HAL drivers
+├── applications    # Flipper applications
+│   └── furi_test   # Test app for checking and demonstrating FURI func
+├── bootloader      # Firmware bootloader, used for `target_f2` and newer
+├── core            # Main feature like OS, HAL (target-independed)
+├── target_f1       # Target-depended code for target F1
+│   ├── Drivers     # STM HAL drivers
 │   │   ├── CMSIS
 │   │   └── STM32L4xx_HAL_Driver
 │   │       ├── Inc
 │   │       │   └── Legacy
 │   │       └── Src
-│   ├── Inc # Autogenerated CubeMX code and target-depended includes
+│   ├── Inc         # Autogenerated CubeMX code and target-depended includes
 │   ├── Middlewares
 │   │   ├── ST
 │   │   │   └── STM32_USB_Device_Library
 │   │   └── Third_Party
 │   │       └── FreeRTOS
-│   └── Src # Autogenerated CubeMX code and target-depended sources
-├── target_lo # Target-depended code for local linux target
+│   └── Src         # Autogenerated CubeMX code and target-depended sources
+├── target_lo       # Target-depended code for local linux target
 │   ├── Inc
 │   └── Src
-└── wiki # Documentation (wiki) generates from this files
+└── wiki            # Documentation (wiki) generates from this files
     ├── applications # info about separate features of flipper
-    ├── fw # core, environment info about firmware
-    └── hw # info about hardware
+    ├── fw          # core, environment info about firmware
+    └── hw          # info about hardware
 ```
 
 # HAL
@@ -48,6 +49,21 @@ Some flipper-specific implementation of gpio/HAL:
 
 Files location: `/app/app_hal.[ch]`
 
+# Bootloader
+
+For production targets('target_f2' and newer) bootloader must be flashed first.
+Detailed instruction on how to compile and flash you can find in `bootloader` fodler.
+
+Production version will have following features:
+
+- Hardware initialization
+- Firmware CRC check
+- Firmware update
+- Interactive UI
+- Boot process LED indicators
+- FS check
+- Recovery mode
+
 # OS
 
 We use FreeRTOS 10.0.1 for sheduling. Documentation available on [freertos.org](https://www.freertos.org/a00106.html).