JP2KAK driver cannot write to /vsimem

[warmerdam]

The JP2KAK driver does not support reading and writing files through VSI*L, and thus does not support in memory or other virtualized dataset access.

[warmerdam]

Implement reading and writing via VSI*L API in trunk (r13918) and added a test (r13917).

Note, the trunk jp2kakdataset now assumes at least Kakadu 4.2.

The read through vsi*l only kicks in if poOpenInfo->fp is NULL. So conventional file access will normally be used, and VSI*L will essentially only be used for virtual files of some sort, or files larger than 2GB (such as VSIFOpen() failed). I did this because there was some evidence that going through VSI*L might be making things slightly slower.

Writing is always through VSI*L for simplicity since performance is likely less of a concern in this case (and the perf. diff is very small anyways).

[warmerdam]

A narrower version of the change which doesn't touch all the KAKADU4 if'defs nor do other cleanup has been applied in the 1.4-esri branch (r13920).

I will attempt to apply a similar change in 1.5 branch...

[warmerdam]

Fixed in 1.5 branch as well (r13921).