set PerMachine to 'yes' to install this in an elevated mode
add a dummy installer so that elevation is only for the NETFX installer
include the MSI package
run the custom installer after the last application
updated tests to use a more correct identifier
let's use the NetFx4Web installer that ships with WiX, it's nice
Merge pull request #195 from github/wix-elevate-when-netfx-missing

Elevate the installer only when Net40 is missing