bug#18097: -m breaks -A

[Paul Eggert]

-m is documented to exclude later matching lines from context, but this 
is nonintuitive and perhaps it should be fixed to not do that. This was 
reported on Savannah a while ago; I'm sending this to bug-grep so that 
it gets a proper bug number.  Please see:

http://savannah.gnu.org/bugs/?28588

for the original bug report, and:

http://lists.gnu.org/archive/html/bug-grep/2010-02/msg00002.html

for Jim Meyering's thoughts about a fix.