Merge pull request dotnet/core-setup#3544 from dotnet-maestro-bot/master-UpdateDepend...
authorMatt Galbraith <MattGal@users.noreply.github.com>
Thu, 21 Dec 2017 22:58:25 +0000 (14:58 -0800)
committerGitHub <noreply@github.com>
Thu, 21 Dec 2017 22:58:25 +0000 (14:58 -0800)
Update BuildTools, CoreClr, CoreFx, WCF to prerelease-02321-01, preview1-26020-03, preview1-26021-02, preview2-26021-02, respectively (master)

Commit migrated from https://github.com/dotnet/core-setup/commit/8a65f59d669e250346a155d8fe488d5ba89b4c86


Trivial merge