Add lastEnabledTime in GetBlobServiceProperties API and minor description update for restoreblobrange (Azure#8920)

Author: xmbms

specification/storage/resource-manager/Microsoft.Storage/stable/2019-06-01/blob.json

@@ -1217,6 +1217,12 @@
           "minimum": 1,
           "maximum": 365,
           "description": "how long this blob can be restored. It should be great than zero and less than DeleteRetentionPolicy.days."
+        },
+        "lastEnabledTime": {
+          "type": "string",
+          "format": "date-time",
+          "readOnly": true,
+          "description": "Returns the date and time the restore policy was last enabled."
         }
       },
       "required": [

specification/storage/resource-manager/Microsoft.Storage/stable/2019-06-01/storage.json

@@ -2564,11 +2564,11 @@
       "properties": {
         "startRange": {
           "type": "string",
-          "description": "Blob start range. Empty means account start."
+          "description": "Blob start range. This is inclusive. Empty means account start."
         },
         "endRange": {
           "type": "string",
-          "description": "Blob end range. Empty means account end."
+          "description": "Blob end range. This is exclusive. Empty means account end."
         }
       },
       "required": [