Fix Beta 1.3-pcg not having correct download link

Author: PhoenixVX

versions/versions.json

@@ -536,7 +536,7 @@
    "server_url": "http://files.betacraft.uk/server-archive/beta/b1.3-1731.jar"
   },
   "b1.3-pcg": {
-   "client_url": "https://mcphackers.github.io/b1.3-pcg.jar",
+   "client_url": "https://mcphackers.github.io/client/b1.3-pcg.jar",
    "proxy_port": 11705,
    "client_timestamp": "2011-03-15T22:00:32Z",
    "resources": "b1.3-pcg.zip"