added new function test_if_data_home_dir() which checks that
path does not contain mysql data home directory.
Using of 'mysql data home'/'any db name' in
DATA DIRECTORY & INDEX DIRECTORY is disallowed
Problem was that there are no support for symlinked files on Windows for
mysqld. So we fail when trying to create them.
Solution: Ignore the DATA/INDEX DIRECTORY clause for partitions and push
a warning. (Just like a MyISAM table)
Merge fix
partition_mgm did not require have_symlink.
Moved the test case to partition_symlink, which
require have_symlink, and should work on both *nix and
Windows
