title: Convert int to value when changing datatype in column
body: <p>Is it possible with liquibase to do some kind of mapping when doing a <code>modifyDataType</code>?</p>
  <p>Considering the following example:</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;changeSet id=&quot;1&quot; author=&quot;me&quot;&gt;
      &lt;createTable tableName=&quot;person&quot;&gt;
          &lt;column name=&quot;id&quot; type=&quot;int&quot;&gt;
              &lt;constraints primaryKey=&quot;true&quot; nullable=&quot;false&quot; /&gt;
          &lt;/column&gt;
          &lt;column name=&quot;firstName&quot; type=&quot;varchar(100)&quot;&gt;&lt;/column&gt;
          &lt;column name=&quot;lastName&quot; type=&quot;varchar(100)&quot;&gt;&lt;/column&gt;
          &lt;column name=&quot;marital_status&quot; type=&quot;int&quot;&gt;
              &lt;constraints nullable=&quot;false&quot; /&gt;
          &lt;/column&gt;
      &lt;/createTable&gt;
  &lt;/changeSet&gt;
  &lt;changeSet id=&quot;2&quot; author=&quot;me&quot;&gt;
      &lt;modifyDataType tableName=&quot;person&quot; columnName=&quot;type&quot;
          newDataType=&quot;varchar(36)&quot; /&gt;
  &lt;/changeSet&gt;
  </code></pre>
  <p>I would like in my column 'type' that the following mapping occurs:</p>
  <pre><code>0-&gt;single
  1-&gt;married
  etc..
  </code></pre>
  <p>Is this possible with liquibase? I'm using it via the command line.</p>