Add git example for release:perform

[ViliusS]

Git doesn't support passing tags in the URL, however I have found that passing -Dtag does the trick.

This still will work only with 2.3.2 and earlier versions because of https://issues.apache.org/jira/browse/MRELEASE-839 , but at least nobody will have to spent 5 hours like me, trying to find why it doesn't work.

• I hereby declare this contribution to be licenced under the Apache License Version 2.0, January 2004

[slawekjaranowski]

Thanks for PR.

I don't see tag parameters for perform goal https://maven.apache.org/maven-release/maven-release-plugin/perform-mojo.html
So how it works ...

[ViliusS]

Good question. I have no idea how this works, it's just what I found only working with 2.3.X series. It still doesn't work with 3.0.0-M5 or 2.2.X.

I guess -Dtag passes the tag to SCM sub-module which is used in 2.3 series, and then sub-module passes this on to git clone command.