BUG: add second baseline to apTvUtQuicklookWithGCP with shifted GCPs because a bug has been fixed in GDAL 3.1.3

REFAC: add second baseline for the DEMToImageGenerator2 test (different no data handling in bilinear resampling)

When using ToJSON attribute to export metadata, the order the metadata
are exported depends on the platform. This is not a problem when
working with metadata, but the test (as they are currently made) need
a constant order of the metadata in the output file.

REFAC: update multi-baseline for large input tests (same projection, but different wkt strings) and removed out-of-date baselines

The application Superimpose crashed with a segmentation fault during
resampling. Investigation revealed that the interpolated index was out
of image bounds. The application uses the PHR mode and resample the XS
image with a otb::GridResampleImageFilter. This filter doesn't check
explicitly that input indexes are in the input buffered region. It
uses a m_ReachableOutputRegion to crop the output region
processed. The problem appears because an output pixel is right on the
border of the input image extent, and when someone uses a nearest neighbor
interpolator, this one converts the continuous index to an
out-of-bound index.

REFAC: Implement the methods ToKeywordlists, ToBandKeywordlists and FromKeywordlists for the class Metadata

PERF: use the move function in the constructors, remplace std::atoi by boost::lexical_cast, use boost::bimap for MDL1DBmType and MDL2DBmType, complete the implementation of ImageMetadataBase::ToKeywordlist for the LUT, use otb::Join

REFAC: LUT1D and LUT2D can now serialize. ToKeywordlist updated to use serialized LUT. Fixed typo Axes to Axis

REFAC: Implementing ImageMetadataBase::FromKeywordlist for StringKeys, NumericKeys, TimeKeys and ExtraKeys. Convertinf the corresponding MDNames to boost::bimap. Fixed missing values in MDNumNames and MDStrNames

REFAC: Implemented parts of the GeometryKeys conversion for ImageMetadataBase::ToKeywordlist. Implemented OTB_GCP, GCPParam and RPCParam.

ENH: Add new Extendded Filename 'epsg' to set the projection of the output image with an EPSG code + tests + doc

BUG: updated multi baselines for ioTvMultiDatasetReading 1 and 2, 'Not specified based on custom spheroid' is not formatted is the same way between different gdal versions

TEST: added multi baseline for ioTvMultiDatasetReading tests when using gdal3 (projection layout is different)