Merge pull request #64 from archlinux/use-own-mirror

Use our own mirror instead

local.json

 {
     "variables": {
 
-    "iso_url": "https://mirror.rackspace.com/archlinux/iso/latest/archlinux-2018.10.01-x86_64.iso",
-    "iso_checksum_url": "https://mirror.rackspace.com/archlinux/iso/latest/sha1sums.txt",
+    "iso_url": "https://mirror.pkgbuild.com/iso/latest/archlinux-2019.10.01-x86_64.iso",
+    "iso_checksum_url": "https://mirror.pkgbuild.com/iso/latest/sha1sums.txt",
     "iso_checksum_type": "sha1",
     "disk_size": "20480",
     "memory": "1024",