ordered data from archive tables

Archive was using wrong memory address to check if field
is NULL (after filesort, when reading record again).

      
This is a backport of the patch for MySQL Bug#50574.
      
Adding a SPATIAL INDEX on non-geometrical columns caused a
segmentation fault when the table was subsequently 
inserted into.
            
A test was added in mysql_prepare_create_table to explicitly
check whether non-geometrical columns are used in a
spatial index, and throw an error if so.
      
For MySQL 5.5 and later, a new and more meaningful error 
message was introduced.  For 5.1, we (re-)use an existing
error code.

The crash happens because Item_cache which is result
holder for Item_subselect can't correctly convert
a DATETIME value from string to int representation.
The fix is to disable constant item convertion for
subselect(partial rollback of bug52157 fix).

An after-fix to workaround different metadata in "mtr --ps" output.

batch_readline_init() was modified - make check for 
type of file for input stream unless target platform
is WINDOWS since on this platform S_IFBLK is undefined.

Reverse DNS lookup of "localhost" returns "broadcasthost" on Snow Leopard (Mac), and NULL on most others.
Simply ignore the output, as this is not an essential part of UDF testing.

batch_readline_init() was modified - return an error
if the input source is a directory or a block device.

This follow-up is necessary because on some platforms,
such as Solaris, call to read() from directory may be
successful.

Resolved an innodb conflict thanks to vasil.

Test failed on a certain Linux platform in automated environment. It turns out that this platform has an old version of Perl modules DBI and DBD::mysql installed, as well as the OS itself being relatively old.
Allowing error code 11 to be returned from mysqlhotcopy on expected error seems harmless and will make the test pass also with older libraries.