New test cases. Names with umlauts don't compare well on Windows.


mysql-test/r/alter_table.result:
  Bug#18775 - Temporary table from alter table visible to other threads
  New test results
mysql-test/r/backup.result:
  Bug#18775 - Temporary table from alter table visible to other threads
  New test results
mysql-test/t/alter_table.test:
  Bug#18775 - Temporary table from alter table visible to other threads
  New test case. Names with umlauts don't compare well on Windows.
mysql-test/t/backup.test:
  Bug#18775 - Temporary table from alter table visible to other threads
  New test case. Names with umlauts don't compare well on Windows.