Improved portability of tests

Removed assumptions about umask and locale. Fixed hostname
tests to work even when the host has no DNS domain set.

Signed-off-by: Dan Fandrich <dan@coneharvesters.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

testsuite/tar.tests

@@ -4,6 +4,12 @@
 
 . ./testing.sh
 
+unset LANG
+unset LANGUAGE
+unset LC_COLLATE
+unset LC_ALL
+umask 022
+
 rm -rf tar.tempdir 2>/dev/null
 mkdir tar.tempdir && cd tar.tempdir || exit 1