cmd: don't alias context package, and use cliContext for cli.Context

Unfortunately, this is a rather large diff, but perhaps worth a one-time
"rip off the bandaid" for v2. This patch removes the use of "gocontext"
as alias for stdLib's "context", and uses "cliContext" for uses of
cli.context.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cmd/ctr/commands/commands_windows.go

@@ -37,6 +37,6 @@ func init() {
 		})
 }
 
-func RuntimeOptions(context *cli.Context) (interface{}, error) {
+func RuntimeOptions(cliContext *cli.Context) (interface{}, error) {
 	return nil, nil
 }