add possibility to edit messages

see #485

src/docs/docs.go

@@ -2040,6 +2040,9 @@ var doc = `{
                         "data:\u003cMIME-TYPE\u003e;filename=\u003cFILENAME\u003e;base64\u003ccomma\u003e\u003cBASE64 ENCODED DATA\u003e"
                     ]
                 },
+                "edit_timestamp": {
+                    "type": "integer"
+                },
                 "mentions": {
                     "type": "array",
                     "items": {

src/docs/swagger.json

@@ -2024,6 +2024,9 @@
                         "data:\u003cMIME-TYPE\u003e;filename=\u003cFILENAME\u003e;base64\u003ccomma\u003e\u003cBASE64 ENCODED DATA\u003e"
                     ]
                 },
+                "edit_timestamp": {
+                    "type": "integer"
+                },
                 "mentions": {
                     "type": "array",
                     "items": {

src/docs/swagger.yaml

@@ -138,6 +138,8 @@ definitions:
         items:
           type: string
         type: array
+      edit_timestamp:
+        type: integer
       mentions:
         items:
           $ref: '#/definitions/client.MessageMention'