Better support for Arch

Arch has both the os-release and arch-release file, make sure we check
for arch first to avoid returning raspbian in that distribution.

os.json

@@ -6,10 +6,10 @@
   "/etc/lsb-release" : ["Ubuntu Linux","Chakra","IYCC","Linux Mint","elementary OS","Arch Linux","Manjaro Linux"],
   "/etc/debian_version" : ["Debian"],
   "/etc/debian_release" : ["Debian"],
+  "/etc/arch-release" : ["Arch Linux"],
   "/etc/os-release": ["Raspbian"],
   "/etc/NIXOS": ["NixOS"],
   "/etc/annvix-release" : ["Annvix"],
-  "/etc/arch-release" : ["Arch Linux"],
   "/etc/arklinux-release" : ["Arklinux"],
   "/etc/aurox-release" : ["Aurox Linux"],
   "/etc/blackcat-release" : ["BlackCat"],