Compilation with older hdf5 interfaces introduces potentially weird versioning issues

[mokus0]

Specifically, the same version of the bindings library can have several different interfaces depending on the version of hdf5 that is being wrapped.

1. Is that a problem?
2. What should be done about it?

One option is to have a different cabal file for each supported version of the hdf5 library. That could make dependency resolution really messy though, depending on how cabal handles pkgconfig dependencies (and whether pkgconfig is even the way to go)

Another option is to just let it be, and let that be something the "high level" wrapper must abstract over.

Another option is to include in the bindings-hdf5 package a "minimal" abstraction over it, which wraps all versions into the same interface (presumably the latest). This seems like the best option overall, but I'm not sure offhand how it should be done. For example, what to do about enumeration constants or macros that don't exist?