title: Phinx migrations - explicit length of integer column
body: <p>Can you tell me please if is possible to set explicit length of integer column via Phinx migrations <code>addColumn()</code> method? </p>
  
  <p>Documentation uses limit option with <code>MysqlAdapter::INT_REGULAR</code> like <code>['limit' =&gt; MysqlAdapter::INT_SMALL, 'signed' =&gt; false]</code> but it automatically sets the length for column e.g. <code>int(10)</code>.</p>
  
  <p>But what should I do if I need <code>int(11)</code> e.g for foreign key column?</p>
  
  <p>Thx.</p>