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/tasks/list.go

@@ -38,9 +38,9 @@ var listCommand = &cli.Command{
 			Usage:   "Print only the task id",
 		},
 	},
-	Action: func(context *cli.Context) error {
-		quiet := context.Bool("quiet")
-		client, ctx, cancel, err := commands.NewClient(context)
+	Action: func(cliContext *cli.Context) error {
+		quiet := cliContext.Bool("quiet")
+		client, ctx, cancel, err := commands.NewClient(cliContext)
 		if err != nil {
 			return err
 		}