document how to patch a zipkin server

[codefromthecrypt]

when building from scratch, you edit the zipkin-server/pom.xml like so.. there's probably value in showing how to do this just using a commandline and an existing zipkin jar. (which would be overriding the classpath I think)

    <!-- Static content for the web UI -->
    <dependency>
      <groupId>${project.groupId}</groupId>
      <artifactId>zipkin-autoconfigure-ui</artifactId>
      <optional>true</optional>
      <exclusions>
        <exclusion>
          <groupId>${project.groupId}</groupId>
          <artifactId>zipkin-ui</artifactId>
        </exclusion>
      </exclusions>
    </dependency>

    <dependency>
      <groupId>io.zipkin.ui</groupId>
      <artifactId>zipkin-ui</artifactId>
      <version>0.0.1</version>
    </dependency>