Solr 删除全部索引:http://localhost:8080/solr/update/?stream.body=<delete><query>*:*</query></delete>&stream.contentType=text/xml;charset=utf-8&commit=true
solr 删除指定ID的索引:http://localhost:8080/solr/update/?stream.body=<delete><id>1</id></delete>&stream.contentType=text/xml;charset=utf-8&commit=true