LANG-378: Indented formatting for ToStringBuilder

Hi all,

I would like to have a recursively indented ToStringStyle for 
readability reasons and found this:
   https://issues.apache.org/jira/browse/LANG-378
   Add new ToStyle to support MultiLine with Indent

I'm willing to pick that up to get the indent that I need.
I know how to refactor stuff while keeping tests green, so this should 
be fun :-)

I have some questions before I start:

- Is there known user interest?
- Is there commitment to reviewing and merging patches?
- LANG-378 has been dormant for almost a decade; is there any hope that 
the patches in it are even useful today?
- Is there any advice about what to do or avoid with ToString and friends?

Any answers appreciated!

Regards,
Jo