Added an Information tag to Attribute

 - add Information for scalar each HDF5 attribute
Merge pull request #104 from c-schumann-zih/topic-hdf5attr

Added an Information tag to Attribute
Made the nodepaths relative by default
Merged advices from the thread in
Merge pull request #107 from c-schumann-zih/topic-splash2xdmfWithRelativeNodepath-2

Made the nodepaths relative by default
Added Funktion to handle filenames from user
Only use hyperslaps if necessary, increase buffers
Use more general h5py::dataset.shape for dims
Merge pull request #110 from ComputationalRadiationPhysics/fix-pythonDimsShape

Use more general h5py::dataset.shape for dims
Merge pull request #109 from ComputationalRadiationPhysics/fix-noFullHyperslaps

Only use hyperslaps if necessary, increase buffers
Integrated a split to seperate grid and poly grids in seperate outputfiles
Compress handle_user_filename and create_xdmf_xml
Fix listFilesInDir
Add subfunction to create_xdmf_xml
Add description fixed time series bug
Change comment
Fix chunking
Add variable for file name length and comment
Merge pull request #112 from ComputationalRadiationPhysics/fix-listFiles

Fix listFilesInDir
Rename var and add description