pdsdataset and isis2dataset updates

[thare]

I have uploaded two upgraded files for pdsdataset.cpp and isis2dataset.cpp. There are changes to the projection section but also many other changes sprinkled through out. Also for the pdsdataset I had to add another routine to check for the cellsize unit

const char *GetKeywordUnit?( const char *pszPath,

int iSubscript, const char *pszDefault = "");

These two .cpp files will need to placed into the new format directory "pds" and change accordingly for the new path. THe old path was "raw". I think there were updates to the NASAKeywordHandler files.

[thare]

ISIS2 enhancements (bug fixes)

[thare]

ISIS2 and PDS enhancements (bug fixes)

[mloskot]

Generated regular patch with changes to isis2dataset.cpp file

[mloskot]

Generated regular patch with changes to pdsdataset.cpp file

[warmerdam]

Patches adjusted slightly and applied in r12801, and r12804 with r12802 restoring PAM support I accidentally lost with r12801 (all in trunk).

While doing this I also took care to remove printf's (in favor of CPLDebug() calls), be careful not to pass CPLString directly to printf() style calls (pass .c_str() instead), and avoid hard exit in isis2dataset.cpp (use CPLError, return NULL).

Closing, and thanks!