georaster - driver does not handle default blocking

[ilucena]

The georaster driver does not assume default values correctly when the blocking parameters are omitted on an existing georaster object on the database.

"""If a value is 0, it means the block size is the corresponding dimension size. If a value is greater than the corresponding dimension size, padding is applied."""

It should say "is 0 or is omitted" like "blockSize(512,512)" for a 3 bands image.

Note that the GDAL/GeoRaster driver always populate those metadata entry.

    <blocking>
      <type>REGULAR</type>
      <totalRowBlocks>20</totalRowBlocks>
      <totalColumnBlocks>20</totalColumnBlocks>
      <totalBandBlocks>3</totalBandBlocks>
      <rowBlockSize>500</rowBlockSize>
      <columnBlockSize>500</columnBlockSize>
      <bandBlockSize>1</bandBlockSize>
    </blocking>

That problem only happens when reading from a georaster loaded by other means.

[ilucena]

Fixed with r20985 that also fix #3805.

If totalRowBlocks is not present it will assume the total number of rows. Same for columns and bands.