• I have searched the issues of this repository and believe that this is not a duplicate.
• I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

• Dubbo version: 2.7.x
• Operating System version: macos
• Java version: 1.7.8

motivation

I checked the consul part of the code and found that some parameters of the configcenter, metadata, and registry modules implemented by consul are the same. Extract these to the common module, and configcenter, metadata, and registry share the same configuration.