Merge branch 'fix-hdf5-errors' into 'master'
Use H5Lexists to check whether /Units exists in IC files before attempting to read them Updated to use H5Lexists to check whether user has input units into their Initial Conditions files. This avoids error rasises from H5G* when opening files without units and reverting back to the ones specified in the parameterfile. We now also let users know when their units are being read from their ICs explicitly. See merge request !427