Request to add options to tools/git_changelog

I am again requesting the addition of options to tools/git_changelog so
I can more easily produce the release notes.  I asked for this during
9.1 development and it was rejected.  I am currently using my own
custom version of the tool, but have to merge community improvements
into the tool every year before I use it.

The attached patch gives you an idea of what I want to add.  New options
are:

    --details-after Show branch and author info after the commit description
    --master-only   Show commits made exclusively to the master branch
    --oldest-first  Show oldest commits first

I know of now to do this with a post-processing script.
 
-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +