ES_DE: adding custom systems support

config/retrodeck/helper_files/es_systems.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<!--
+This is an example of a custom system, you can add as many as you want by following this template.
+More info on the official ES-DE Documentation:
+https://gitlab.com/es-de/emulationstation-de/-/blob/master/USERGUIDE.md#game-system-customizations
+-->
+<systemList>
+    <!--
+    <system>
+        <name>mysystem</name>
+        <fullname>An example fake system</fullname>
+        <path>%ROMPATH%/mysystem</path>
+        <extension>.bin .BIN .chd .CHD .cue .CUE .iso .ISO .7z .7Z .zip .ZIP</extension>
+        <command label="MyEmulator">%EMULATOR_SOMETHING% %ROM%</command>
+        <platform>mysystem</platform>
+        <theme>mysystem</theme>
+    </system>
+    -->
+</systemList>

config/retrodeck/reference_lists/features.json

@@ -168,6 +168,10 @@
     "ryujinx_firmware": {
       "filename": "Install-firmware-through-Ryujinx.txt",
       "location": "$bios_folder/switch/firmware"
+    },
+    "custom_systems": {
+      "filename": "es_systems.xml",
+      "location": "$rdhome/ES-DE/custom_systems/es_systems.xml"
     }
   },
   "compression_targets": {

functions/prepare_component.sh

@@ -66,6 +66,7 @@ prepare_component() {
       set_setting_value "$es_settings" "UserThemeDirectory" "$themes_folder" "es_settings"
       dir_prep "$rdhome/ES-DE/gamelists" "/var/config/ES-DE/gamelists"
       dir_prep "$rdhome/ES-DE/collections" "/var/config/ES-DE/collections"
+      dir_prep "$rdhome/ES-DE/custom_systems" "/var/config/ES-DE/custom_systems"
       dir_prep "$rd_logs_folder/ES-DE" "$es_source_logs"
       log d "Generating roms system folders"
       #es-de --home /var/config/ES-DE --create-system-dirs