This patch does proper quoting, and uses "env" to be compatible with
tcsh.  As a side benefit, I believe the code is a lot cleaner to read.

[jc: I am accepting this not because I necessarily agree with the
 quoting approach taken by it, but because (1) the code is only used
 by ssh-fetch/ssh-upload pair which I do not care much about (if you
 have ssh account on the remote end you should be using git-send-pack
 git-fetch-pack pair over ssh anyway), and (2) HPA is one of the more
 important customers belonging to the Linux kernel community and I
 want to help his workflow -- which includes not wasting his time by
 asking him to switch to git-send-pack/git-fetch-pack pair, nor to use
 a better shell ;-).  I might not have taken this patch if it mucked
 with git_connect in connect.c in its current form.]
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>