Merge pull request #289 from jiaoshuntian/master

update contribution guides

Author: gaoxueyu

CN/modules/ROOT/nav.adoc

@@ -81,7 +81,7 @@
 * 数据迁移
 ** xref:master/migration_guide.adoc[迁移指南]
 * IvorySQL开发者
-** xref:master/contribution/community_contribution_guide.adoc[社区贡献指南]
+** xref:master/contribution/contribution_guide.adoc[贡献指南]
 ** xref:master/developer_guide.adoc[开发者指南]
 ** IvorySQL架构设计
 *** 查询处理