feat: Add serializer for Histotable used by HighestUriPrecedenceProvider

[adam-miller]

This fixes an issue when using the HighestUriPrecedenceProvider where the nested generics in the Histotable fail to serialize properly.

Sample config:

  <bean id="frontier" class="org.archive.crawler.frontier.BdbFrontier">
    <property name="queuePrecedencePolicy">
      <bean class="org.archive.crawler.frontier.precedence.HighestUriQueuePrecedencePolicy"/>
    </property>
    <property name="maxRetries" value="40"/>
    <property name="retryDelaySeconds" value="180"/>
    <property name="dumpPendingAtClose" value="true"/>
  </bean>

[adam-miller]

I'm left with the following warning:

00:02  WARN: Class is not registered: org.archive.crawler.frontier.precedence.HighestUriQueuePrecedencePolicy$HighestUriPrecedenceProvider
Note: To register this class use: kryo.register(org.archive.crawler.frontier.precedence.HighestUriQueuePrecedencePolicy.HighestUriPrecedenceProvider.class);

However, this class is in the engine subproject and importing it into KryoBinding would create a circular dependency. I see that other classes such as BdbWorkQueue seem to get around this with an autoregisterTo() method, but I'm not clear on how to get this to get that function called if implemented in HighestUriQueuePrecedencePolicy