title: Convert Avro file to JSON with reader schema
body: <p>I would like to deserialize Avro data on the command line <em>with a reader schema that is different from the writer schema</em>. I can specify writer schema on serialization, but not during deserialization.</p>
  
  <p><code>record.json</code> (data file):</p>
  
  <pre><code>{"test1": 1, "test2": 2}
  </code></pre>
  
  <p><code>writer.avsc</code> (writer schema):</p>
  
  <pre><code>{
      "type": "record",
      "name": "pouac",
      "fields": [
          {
              "name": "test1",
              "type": "int"
          },
          {
              "name": "test2",
              "type": "int"
          }
      ]
  }
  </code></pre>
  
  <p><code>reader.avsc</code> (reader schema):</p>
  
  <pre><code>{
      "type": "record",
      "name": "pouac",
      "fields": [{
          "name": "test2",
           "type": "int",
           "aliases": ["test1"]
      }]
  }
  </code></pre>
  
  <p>Serializing data:</p>
  
  <pre><code>$ java -jar avro-tools-1.8.2.jar fromjson --schema-file writer.avsc record.json &gt; record.avro
  </code></pre>
  
  <p>For deserializing data, I tried the following:</p>
  
  <pre><code>$ java -jar avro-tools-1.8.2.jar tojson --schema-file reader.avsc record.avro
  Exception in thread "main" joptsimple.UnrecognizedOptionException: 'schema-file' is not a recognized option
  ...
  </code></pre>
  
  <p>I'm looking primarily for a command line instruction because I'm not so confortable writing Java code, but I'd be happy with Java code to compile myself. Actually, what I'm interested in is the exact deserialization result. (the more fundamental issue at stake is described in <a href="https://github.com/tebeka/fastavro/pull/113#pullrequestreview-77570134" rel="nofollow noreferrer">this conversation</a> on a fastavro PR that I opened to implement aliases)</p>