Updates for XIOS outputs. NMC outputs now OK, as long as these are in output files number 6 and more (phys_out_filenames ordering in config.def).
Among things that need be worked on further with XIOS:
Station outputs form and format.
Extra axes can only be included in XIOS files if linked to given variables.
Further splitting of the XML files as iodef.xml, context_lmdz.xml,
field_def_lmdz.xml and file_def_hist*_lmdz.xml.