[Feature#3961]Registry SPI
All the logical structure of the registry must be converted into a tree structure within the system, so some plug-ins must be converted internally, such as ETCD
The registry supports distributed locks.
todo: The specific information about the registration center of the API module needs to be adjusted.
* Optimize dependencies between modules.
* update module-alert dependency.
* add repository in the pom xml.
* update Central Repository in the pom.xml.
* [Improvement][*] Update version to 1.4.0-SNAPSHOT
* [Improvement][*] Update tab to space under checkstyle
* [Improvement][*] Define version with revision globally
* [Improvement][*] Update version to 1.3.6-SNAPSHOT
Kirs
zhuangchong
Shiwen Cheng
felix.wang
CalvinKirs