Change namespace to add Kanboard as prefix

app/Schema/Mysql.php

@@ -3,8 +3,8 @@
 namespace Schema;
 
 use PDO;
-use Core\Security;
-use Model\Link;
+use Kanboard\Core\Security;
+use Kanboard\Model\Link;
 
 const VERSION = 91;
 

app/Schema/Postgres.php

@@ -3,8 +3,8 @@
 namespace Schema;
 
 use PDO;
-use Core\Security;
-use Model\Link;
+use Kanboard\Core\Security;
+use Kanboard\Model\Link;
 
 const VERSION = 71;
 

app/Schema/Sqlite.php

@@ -2,9 +2,9 @@
 
 namespace Schema;
 
-use Core\Security;
+use Kanboard\Core\Security;
 use PDO;
-use Model\Link;
+use Kanboard\Model\Link;
 
 const VERSION = 86;