update readme (#49)

server/README.md

@@ -377,30 +377,31 @@ mutation {
 }
 ```
 
-### `addTopic`
-Adds a new topic.
+### `addLabel`
+Adds a new event label. `kind` takes `TOPIC` or `EVENT_TYPE` as value.
 #### Arguments:
-- `topic: NewTopic!` - Details of the new topic.
+- `label: NewLabel!` - Details of the new label.
 
 #### Example:
 ```graphql
 mutation {
-  addTopic(topic: {
+  addLabel(topic: {
     name: "Physics"
     color: "#FF0000"
+    kind: TOPIC
   })
 }
 ```
 
-### `deleteTopic`
-Deletes a list of topics. *Note: This also deletes all events related to it*
+### `deleteLabel`
+Deletes a list of labels. *Note: This also deletes all events related to it*
 #### Arguments:
-- `name: [String!]!` - Names of topics
+- `name: [String!]!` - Names of labels
 
 #### Example:
 ```graphql
 mutation {
-  deleteTopic(name: "Math")
+  deleteLabel(name: "Math")
 }
 ```