pull up r19541 from trunk

pull up r19541 from trunk

 r19541@cathode-dark-space:  jaltman | 2007-05-03 18:57:05 -0400
 ticket: new
 subject: Modify WIX installer to better support upgrading betas
 component: windows
 tags: pullup

 The WIX installers did not upgrade previous installations with the same
 version number as the current package being installed.  This would leave
 multiple installations of KFW x.y.z registered as being installed on the
 machine even though only the most recent install is being used.

 This commit instructs the Windows Installer to uninstall previous installations
 with the same version number (the Maximum Upgrade version) as the package
 that is being installed while ensuring that the package being installed
 will not be uninstalled if the installation is being modified or repaired.

ticket: 5554
version_fixed: 1.6.2

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-6@19591 dc483132-0cff-0310-8789-dd5450dbe970