Remove the hello world, Add generic string text reference

shell/android/res/values-jp/strings.xml

 <resources>
 
     <string name="app_name">reicast</string>
-    <string name="hello_world">Hello world!</string>
     <string name="menu_settings">セッティング</string>
     <string name="title_activity_main">reicast</string>
     <string name="system_path">システムパス (とのデータフォルダーの場所 dc_boot.bin/dc_flash.bin)</string>

shell/android/res/values-pt/strings.xml

 <resources>
 
     <string name="app_name">reicast</string>
-    <string name="hello_world">Hello world!</string>
     <string name="menu_settings">Configurações</string>
     <string name="title_activity_main">reicast</string>
     <string name="system_path">Caminho Sistema (localização da pasta de dados com dc_boot.bin / dc_flash.bin dentro)</string>

shell/android/res/values/strings.xml

 <resources>
 
     <string name="app_name">reicast</string>
-    <string name="hello_world">Hello world!</string>
     <string name="menu_settings">Settings</string>
     <string name="title_activity_main">reicast</string>
     <string name="system_path">System Path (location of the data folder with dc_boot.bin/dc_flash.bin inside)</string>

shell/android/strings.txt

+{\rtf1\ansi\ansicpg1252\cocoartf1265
+{\fonttbl\f0\fnil\fcharset0 Monaco;}
+{\colortbl;\red255\green255\blue255;}
+\margl1440\margr1440\vieww10800\viewh8400\viewkind0
+\deftab720
+\pard\pardeftab720
+
+\f0\fs22 \cf0 Settings\
+reicast\
+System Path (location of the data folder with dc_boot.bin/dc_flash.bin inside)\
+Default System Path\
+Storage Path (location of .gdi, .chd or .cdi images)\
+Default Game Storage\
+Boot Dreamcast Bios\
+BIOS Missing. The Dreamcast BIOS is required for this emulator to work. Place the BIOS file in ####/data/dc_boot.bin\
+Flash Missing. The Dreamcast Flash is required for this emulator to work. Place the Flash file in ####/data/dc_flash.bin\
+You have to provide the BIOS\
+BOOT BIOS\
+SELECT CURRENT FOLDER\
+Dynarec Options\
+Unstable Optimisations\
+DC Region\
+Limit FPS\
+Use Mipmaps (fix for old SGX540)\
+Widescreen Mode\
+Frameskip Value\
+PVR Rendering (does nothing for now)\
+Set Default Disk\
+Available Dreamcast Games\
+Customize Touch Controls\
+Launch Editor\
+Touch Vibration\
+Controller A\
+Controller B\
+Controller C\
+Controller D\
+Controller Not Connected\
+No Controller Selected\
+Select\
+Remove\
+Select Controller\
+Press any button on the controller #### to assign to port\
+This controller is already in use!\
+Enable Custom Key Layout\
+Enable Compatibility Mode\
+Customize Physical Controls\
+Modify Controller\
+Press the new controller button for ####\
+MOGA Pro Connected!\
+MOGA Connected!\
+About reicast\
+reicast is a dreamcast emulator\\n\\nVersion: ####\
+Controller A\
+Controller B\
+Controller C\
+Controller D\
+(Default)\
+Slider Menu Opened\
+Slider Menu Closed\
+Browser\
+Settings\
+Paths\
+Input\
+About\
+Rate Me\
+Item Icon\
+ON\
+OFF\
+Save Error Logs}
\ No newline at end of file