Updated Tiered Storage (markdown)

Tiered-Storage.md

@@ -27,6 +27,12 @@ fs.configure -locationPrefix=/buckets/ssd_ -disk=ssd -apply
 
 https://github.com/chrislusf/seaweedfs/wiki/Path-Specific-Configuration
 
+# Customizable Tags for Disk Type
+
+Custom Tags are supported for the disk types. Besides the default `hdd` and `ssd`, you can use any lower-cased tags, such as `ssd1`, `hdd2`, `nvme`, `raid6`, etc.
+
+You can also schedule admin scripts to move volumes from one tier to another tier. See below for `volume.tier.move`.
+
 ## Change Volume Disk Type
 
 When `volume.balance` or `volume.fix.replication`, the volume disk type would not change.