Began working on dir.Mknod.
Began working on dir.Mknod.

jacobsa/ratelimit,GoogleCloudPlatform/gcsfuse,GoogleCloudPlatform/gcsfuse,BanzaiMan/gcsfuse,mbrukman/gcsfuse,jacobsa/timeutil,GoogleCloudPlatform/gcsfuse,kahing/gcsfuse,BanzaiMan/gcsfuse