gettext tests: rename test to work around GNU gettext bug

gettext tests: rename test to work around GNU gettext bug

Rename t0200-gettext.sh to t0200-gettext-basic.sh. Versions of GNU
gettext before v0.15 (released in 2006) fail to run the test because
of an old bug in gettext.sh.

To conform with the FHS gettext.sh prints a help message when it's
invoked directly. To do this it checks if $0 is "gettext.sh". This
check was broken before v0.15, it was checking for *\gettext.sh (to
support Windows), but now correctly checks for *\\gettext.sh.

t0200-gettext.sh matched the former broken check, so on systems with
an old GNU gettext (like RHEL 5.4) the test simply printed:

    ./t0200-gettext.sh
    GNU gettext shell script function library version 0.14.6
    Usage: . gettext.sh
    FATAL: Unexpected exit with code 1

Which is just the gettext.sh help output:

    $ gettext.sh
    GNU gettext shell script function library version 0.17
    Usage: . gettext.sh

Change the test name to t0200-gettext-basic.sh to work around that.

Reported-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Tested-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>