New request guard: Authorization<Action, Scope>

Filter requests that don't have an API token authorized to read or write
a specific scope;

src/api/mod.rs

@@ -51,4 +51,5 @@ fn oauth(query: OAuthRequest, conn: DbConn) -> Json<serde_json::Value> {
 }
 
 pub mod apps;
+pub mod authorization;
 pub mod posts;