Groovy Builder AST merged to Groovy Core!

Hi!

Today it turned out that Paul King merged the Builder AST transform that based on my PojoBuilder to core of Groovy. So you will be able to use it when the new version of Groovy gets released.

You can take a look at the code here

https://github.com/groovy/groovy-core/pull/389

Many thanks go to Marcin Zajączkowski for his code review to the initial version.

It's not the biggest features in the world but anyway, enjoy :)