Maven配置阿里云镜像

<mirrors><!-- 阿里云Maven镜像配置 --><mirror><id>nexus-aliyun</id><mirrorOf>*</mirrorOf><name>Nexus aliyun</name><url>http://maven.aliyun.com/nexus/content/groups/public</url></mirror>    <!-- mirror     | Specifies a repository mirror site to use instead of a given repository. The repository that     | this mirror serves has an ID that matches the mirrorOf element of this mirror. IDs are used     | for inheritance and direct lookup purposes, and must be unique across the set of mirrors.     |    <mirror>      <id>mirrorId</id>      <mirrorOf>repositoryId</mirrorOf>      <name>Human Readable Name for this Mirror.</name>      <url>http://my.repository.com/repo/path</url>    </mirror>     -->  </mirrors>