Remove keep_factory_alive startup call from ShenEOS; add shutdown call to H5close

[brycelelbach]

[reported by blelbach] [Trac time Fri Apr 20 21:53:57 2012] Due to issues described in #389, we have to disable HDF5's normal shutdown routines. ShenEOS needs to register a call to the cleanup function H5close() via a shutdown function. We should also drop the keep-alive call that we added to ShenEOS to try and resolve this problem.