STunney/BobArnson: WIXFEAT:4239

Add option to not extract the .msi when melting .wixpdbs. Don't leave temporary cabinet files behind (unless -notidy is in effect).
Per feedback. Restore Common.DeleteTempFiles and wrap it in AppCommon instead.
Merge pull request #7 from barnson/feature4239

STunney/BobArnson: WIXFEAT:4239