Bugfix and added new routines

Default settings can be set via ncdf_default.
  Currently it allows ACCESS, and COMPRESS_LVL
Changed ncdf_var_par_access to ncdf_par_access
  If var-name not given, it will set it for all variables
  If var-name is given, it will only set it for that variable.

If the file is parallel then the compression level will always be 0.