Revendor github.com/Microsoft/hcsshim

1. Revendors github.com/Microsoft/hcsshim to the latest known good commit.
This includes numerous bug fixes and improvements.

2. Vendors indirect dependency on go.opencensus.io since hcsshim now uses trace
correlation.

Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>

vendor/github.com/Microsoft/hcsshim/internal/oc/span.go

@@ -0,0 +1,17 @@
+package oc
+
+import (
+	"go.opencensus.io/trace"
+)
+
+// SetSpanStatus sets `span.SetStatus` to the proper status depending on `err`. If
+// `err` is `nil` assumes `trace.StatusCodeOk`.
+func SetSpanStatus(span *trace.Span, err error) {
+	status := trace.Status{}
+	if err != nil {
+		// TODO: JTERRY75 - Handle errors in a non-generic way
+		status.Code = trace.StatusCodeUnknown
+		status.Message = err.Error()
+	}
+	span.SetStatus(status)
+}