remote-helpers/test-bzr.sh: do not use "grep '\s'"

Using grep "devel\s\+3:" to find at least one whitspace is not
portable on all grep versions; not all grep versions understand "\s"
as a "whitespace".

Use a literal TAB followed by SPACE.

The + as a qualifier for "one or more" is not a basic regular
expression; use egrep instead of grep.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
remote-hg: activate graphlog extension for hg_log()

The hg_log() test helper uses the "--graph" parameter that is
implemented by the GraphLog extension. If the extension is not activated
by the user, the parameter is not available. Activate the extension in
setup().

Also changes the way we grep the output in hg_log(). The pipe operator
can hide the return code of hg command. As a matter of fact, if log
fails because it doesn't know about "--graph", it doesn't report any
failure and let's you think everything worked.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>