Obscure commit message formatting issue

The current code drops extra blank lines between the first line of a 
commit message (the summary line) and the remainder. That is:

This is the summary


This is another bit


This is a third bit

turns into:

Subject: This is the summary
Other-Headers:

This is another bit


This is a third bit


This is an issue if you want to generate an email whose body starts with a 
blank line, and I assume (although I haven't tried), that rebase would 
lose a blank line out of commits formatted like that. We don't seem to 
have any tests that require that line to get suppressed, and we also don't 
suppress any other blank lines. Is there some reason to do it?

I'd guess that the "first" handling in pp_remainder() was intended to skip 
the blank line between the summary line and the body, but that line has 
already been consumed by other code.

	-Daniel
*This .sig left intentionally blank*