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/schema2/silo_properties.go

@@ -11,7 +11,6 @@ package hcsschema
 
 //  Silo job information
 type SiloProperties struct {
-
 	Enabled bool `json:"Enabled,omitempty"`
 
 	JobName string `json:"JobName,omitempty"`