git commit message conventions

[Paul Eggert]

Joseph Myers wrote:
> I propose that we adopt standard git commit message conventions that: the
> first line of a commit message is a short description of the commit, the
> next line is a blank line, and the rest of the commit message is the
> detailed description / rationale for the patch

Many other GNU projects use this style, but with one further constraint: if you 
indent the entire commit message, and omit the 2nd (empty) line, the entire 
commit message must be a valid ChangeLog entry.  That way, there's a one-to-one 
relationship between commit messages and ChangeLog entries, and programs like 
vc-dwim can be used to generate commits.  Projects that use such a style include 
Coreutils, Gnulib, and GNU Emacs.  I suggest using it for glibc as well.