Rewrite to a API trait.

gamenight-api-client-rs/src/models/gamenight.rs

@@ -17,6 +17,8 @@ pub struct Gamenight {
     pub id: String,
     #[serde(rename = "name")]
     pub name: String,
+    #[serde(rename = "location_id", skip_serializing_if = "Option::is_none")]
+    pub location_id: Option<String>,
     #[serde(rename = "datetime")]
     pub datetime: String,
     #[serde(rename = "owner_id")]
@@ -28,6 +30,7 @@ impl Gamenight {
         Gamenight {
             id,
             name,
+            location_id: None,
             datetime,
             owner_id,
         }