estimate.json in sk_api_schema-0.0.15

- old
+ new

@@ -34,10 +34,14 @@
       "description": "Defaults to draft for new documents, if empty. For new documents with status 'open', the following fields are set if empty: number(next in number schema), date(today), due date(today unless due_days given). Only drafts can be deleted.",
       "default":"draft",
       "enum":["draft","open","closed"],
       "type":"string"
     },
+    "external_ref":{
+      "description": "Some external reference, whatever this may be.",
+      "type":"string"
+    },
     "title":{
       "description": "The headline of a document. Use SK placeholders to prevent exessive typing e.g. 'Your estimate [number]'",
       "type":"string"
     },
     "notes_before":{
@@ -96,10 +100,9 @@
       "readonly":true,
       "type":"string"
     },
     "lock_version":{
       "description": "Auto-incremented to prevent concurrent updateing. First save wins and increments version.",
-      "optional":true,
       "type":"integer"
     },
     "gross_total":{
       "description": "Gross total of all line items, 2 decimals places",
       "readonly":true,