http://m2eclipse.sonatype.org/sites/m2e地址更换了

http://m2eclipse.sonatype.org/sites/m2e

更换为 https://repository.sonatype.org/content/sites/forge-sites/m2e/ 里面有各个版本对应的链接

常用版本链接： https://repository.sonatype.org/content/sites/forge-sites/m2e/0.12.2/S/0.12.2.20110415-2017/