SYMPHONY-1697 Improved build fast-fail (msbuild and tests).
SYMPHONY-1699 Workaround for IIS/PowerShell issue http://forums.iis.net/t/1159761.aspx (PowerUpWeb).
+minor code reordering
SYMPHONY-1699 Added 'aftercopy' hook to the Invoke-Combo-StandardWebsite.
SYMPHONY-1704 Made test root configurable and enabled v2 mixed-mode assemblies.
SYMPHONY-1715 Improved logging in PowerUpFileSystem/Copy-FilteredDirectory.
SYMPHONY-1719 Added robust delete to PowerUp (Remove-DirectoryFailSafe).
Also includes some previously lost logging changes.