Merge remote-tracking branch 'gh/cpp-formatreader' into cpp-newbase
Merge remote-tracking branch 'gh/cpp-model-fixes' into cpp-newbase
Merge remote-tracking branch 'gh/cpp-pedantic-long-long' into cpp-newbase
cmake: Enable clang++ docstring checking
cmake: Enable -Wextra warnings

This requires fixing of all the warnings in static and generated code.
cmake: Enable -Wconversion warnings

Fix all type conversion warnings.  This also required changing
the size of some of the base types used e.g. pixel_size_type.