Adding ctr memory and cpu flags

Adds ctr run --memory-limit for all platforms.
Adds ctr run --cpu-count for Windows platforms.

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

cmd/ctr/commands/commands_windows.go

@@ -0,0 +1,30 @@
+// +build windows
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package commands
+
+import (
+	"github.com/urfave/cli"
+)
+
+func init() {
+	ContainerFlags = append(ContainerFlags, cli.Uint64Flag{
+		Name:  "cpu-count",
+		Usage: "number of CPUs available to the container",
+	})
+}