Merge pull request dotnet/coreclr#8909 from gkhanna79/Docker1404
authorGaurav Khanna <gkhanna@microsoft.com>
Thu, 12 Jan 2017 18:11:44 +0000 (10:11 -0800)
committerGitHub <noreply@github.com>
Thu, 12 Jan 2017 18:11:44 +0000 (10:11 -0800)
Add optional argument to skip unmount for rootfs

Commit migrated from https://github.com/dotnet/coreclr/commit/a33f44f70a992f153d7fd27c840661978ce1e0f4


Trivial merge