In most cases the names aren't even supported/used and thus it is
wasteful to have them in all *Data classes. If the importer wants to
support them, it would reimplement *name() functions instead.
Some functions need to return "invalid ID", which in case of size_t
cannot be -1.
Also the plugins should behave the same in 32/64bit systems, so the type
should be the same for both.
AbstractImporter now provides access to the data directly and doesn't
attempt to do any OpenGL stuff, thus making everything more transparent
and testable.
Start of AbstractImporter rework - Trade namespace will contain simple
classes usable for exchanging data with other formats, importers will
not depend on any OpenGL functionality, they will just provide access to
plain data.
Each importer must now specify whether it can open files or streams in
features() and implement one or both open() functions. Default
implementation of open() functions now prints message on error output
and returns false.
SizeTraits class provides suitable types for given data size at compile
time, SizeBasedCall can call suitable templated overload based on given
data size at runtime.
Also added meta classes Pow and Log for computing powers and logarithms
at compile time, usable mainly in conjunction with SizeTraits. Their
implementation is checked at compile-time using static_cast().