Merge branch 'maint'

* maint:
  t/t7500-commit.sh: use test_cmp instead of test
  t/gitweb-lib.sh: Ensure that errors are shown for --debug --immediate
  gitweb/gitweb.perl: don't call S_ISREG() with undef
  gitweb/gitweb.perl: remove use of qw(...) as parentheses