Changes

'''Background''' The hosts on my network are a mix of 7-Zip (various revisionversions) .exe and .msi based installs.Use this if you have existing .exe based installs of 7-Zip (such as 4.20) and you would like to uninstall them before switching to an .msi based install. If you do a .msi based install without first uninstalling the .exe version it will leave some files from the .exe based install intact as well as an entry in "Add/Remove Programs". Use this if you have existing .exe based installs of 7-Zip (such as 4.20) and you would like to uninstall them before switching to an .msi based install.