Add serranoltexx on readme & rename config

Author: freechelmi

README.md

@@ -77,6 +77,7 @@ Samsung | Galaxy A3 2017 | a3y17lte | SM-A320FL | tested
 Samsung | Galaxy S III Neo | s3ve3g | GT-I9301I | tested
 Samsung | Galaxy A5 2016 | [a5xelte](https://wiki.lineageos.org/devices/a5xelte/) | SM-A510F | tested
 Samsung | Galaxy A7 2016 | a7xelte | | tested
+Samsung | Galaxy S4 Mini | [serranoltexx](https://wiki.lineageos.org/devices/serranoltexx/) | | tested
 Samsung | Galaxy S6 | [zerofltexx](https://wiki.lineageos.org/devices/zerofltexx/) | | tested
 Samsung | Galaxy S6 Edge | [zeroltexx](https://wiki.lineageos.org/devices/zeroltexx/) | | tested
 Samsung | Galaxy S7 | [herolte](https://wiki.lineageos.org/devices/herolte/) | SM-G930F | tested

openandroidinstaller/assets/configs/serranoltexx.yaml

@@ -0,0 +1,26 @@
+metadata:
+  maintainer: Michel Memeteau (freechelmi)
+  device_name: Samsung Galaxy S4 Mini (2013)
+  is_ab_device: false
+  device_code: serranoltexx
+  supported_device_codes:
+    - serranolte
+    - serranoltexx
+steps:
+  unlock_bootloader:
+  boot_recovery:
+    - type: call_button
+      content: >
+        As a first step, you need to boot into the bootloader. A bootloader is the piece of software, 
+        that tells your phone who to start and run an operating system (like Android). Your device should be turned on. 
+        Then press 'Confirm and run' to reboot into the bootloader. Continue once it's done.
+      command: adb_reboot_download
+    - type: call_button
+      content: In this step, you need to flash a custom recovery on your device. Press 'Confirm and run' to start the process. Confirm afterwards to continue.
+      command: heimdall_flash_recovery
+    - type: confirm_button
+      img: samsung-buttons.png
+      content: >
+        Unplug the USB cable from your device. Then manually reboot into recovery by pressing the *Volume Down* + *Power buttons* for 8~10 seconds 
+        until the screen turns black & release the buttons immediately when it does, then boot to recovery with the device powered off, 
+        hold *Volume Up* + *Home* + *Power button*.