hdf5_ep

Merge pull request #1051 in HDFFV/hdf5 from ~BMRIBLER/hdf5_1_8_bmr:hdf5_1_8 to hdf5_1_8

Improvement regarding to Exception hierarchy and throwException.

* commit '5e4bc6df758b1dffad3583391e51e3c71bb91501':
  C++ API improvement Description:     - Reorganized some exception classes to reflect the HDF5 object       hierarchy and provide extendibility.         DataSetIException -> LocationException -> Exception         DataTypeIException -> LocationException -> Exception         GroupIException -> LocationException -> Exception         AttributeIException -> LocationException -> Exception         FileIException -> GroupIException -> LocationException -> Exception     - Added throwException() to these subclasses and use it in H5Location         and H5Object member functions to throw an exception that is specific         to the object that invokes the member function.  Applications that         catch the base exception can continue to do the same.     - Many cleanup for inconsistencies in comments/headers. Platforms tested:     Linux/64 (jelly)     Linux/64 (platypus)     Darwin (osx1010test)