This commit adds some command line options to the invocation of `git'
in `vc-git-grep' so that git disables all coloring and paging. Without
this, I get a warning about my "terminal" not being fully functional
and git-grep attempts to use a pager (which means the git-grep process
never finishes):

    git grep -n -e stuff -- *
    WARNING: terminal is not fully functional
     CREDITS:14:D: Alpha systems hacking, IPv6 and other network related stuff
    <snip>
    :  <-- pager waiting for me to do something



-- 
"if i had more time i would have written a shorter letter."
--Pascal