Get chdir.t working under minitest

minitest can run before everything is built.

chdir.t used to take that into account, but was not updated when dist/Cwd/
was renamed.
Get closure.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.  Also, we need to make sure that, when run from TEST, we
do actually include buildcustomize.pl.
Get eval.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get lc.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get sub.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get taint.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get tr.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get pat_re_eval.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get reg_eval_scope.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get rxcode.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/cache.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/class.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/fold.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/gv.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/labels.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/lower.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/title.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/uni/upper.t working under minitest

minitest can run before everything is built.  Hence, we need to make sure
the directories that buildcustomize.pl puts in @INC are not clobbered by
the test script.
Get t/comp/hints.t working under miniperl

As of commit 2db3e09128, compiling /\x{100}/i is an error in miniperl
if Unicode tables have not been loaded yet.  This can happen in
minitest if things are broken enough that make_ext.pl cannot run.
Get t/io/fs.t working under miniperl

If things are broken enough that make_ext.pl cannot run, then mini-
test may run this script before Errno.pm is generated and copied
into lib/.