Add comments back to files!

[aadrian]

A newly generated Grails 2.5.x project had many useful comments in DataSource.groovy, BuildConfig.groovy and Config.groovy.

Grails 3.3.3 has for the most part none of those in the corresponding new files :( .

Those comments were very useful to:

• see what options were possible
• just comment/uncomment some settings quickly
• see what's the right place to do something (or just search for it since there's a placeholder in the comment)
• avoid many newbie questions and unnecessary confusion.

Please add them back.

Thank you.

[niravassar]

Thank you. can you please submit a PR with some specifics in the files that you would find useful?

Thanks.