Fixes

schema.sql

@@ -1,6 +1,6 @@
 CREATE TABLE IF NOT EXISTS Players (
-  email TEXT PRIMARY KEY,
-  username TEXT UNIQUE,
+  username TEXT PRIMARY KEY,
+  email TEXT UNIQUE,
   digest BLOB,
   data BLOB,
   activation_code TEXT,
@@ -13,5 +13,5 @@ CREATE TABLE IF NOT EXISTS SignedInUsers (
   player TEXT,
   created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
   last_used_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
-  FOREIGN KEY (player) REFERENCES Players (email) ON DELETE CASCADE
+  FOREIGN KEY (player) REFERENCES Players (username) ON DELETE CASCADE
 );