update the URL to the install.sh, it's in provision now

INSTALL.txt

@@ -203,7 +203,7 @@ installing the right packages and preparing the Drupal frontend install for
 you. That script needs to be run as the aegir user created above.  This file
 is available alongside this one or can be downloaded through the web at:
 
-http://git.aegirproject.org/?p=hostmaster.git;a=blob_plain;f=install.sh.txt;hb=HEAD
+http://git.aegirproject.org/?p=provision.git;a=blob_plain;f=install.sh.txt;hb=HEAD
 
 By default, the install script will install the "correct" version of Aegir
 (ie. if it was downloaded through git, it will install the version from the