[API] GDALRasterBand: add convenience ReadRaster() methods

[rouault]

(on top of bugfix #10468)

/** Read a region of image data for this band.
 *
 * This is a slightly more convenient alternative to GDALRasterBand::RasterIO()
 * for common use cases, like reading a whole band.
 * It infers the GDAL data type of the buffer from the C/C++ type of the buffer.
 * This template is instantiated for the following types: [u?]int[8|16|32|64]_t,
 * float, double, std::complex<float|double>.
 *
 * To read a whole raster (assuming it fits into memory), as a vector of double:
 *
\code
 std::vector<double> myArray;
 if (poBand->ReadRaster(myArray) == CE_None)
 {
    // do something
 }
\endcode
 *
 * To read 128x128 pixels starting at (col=12, line=24) as a vector of double:
 *
\code{.cpp}
 std::vector<double> myArray;
 if (poBand->ReadRaster(myArray, 12, 24, 128, 128) == CE_None)
 {
    // do something
 }
\endcode
 *

[coveralls]

coverage: 69.31% (+0.02%) from 69.295%
when pulling a3f9d6d on rouault:ReadPixels
into 3122857 on OSGeo:master.

[mdsumner]

Nice, much appreciated