=========================================================================
  FUNCTION [ nx, nz, data] = load2Dbin( fpath, fname);
  This function simply loads a 2D matrix from a binary file. It requires
  the following info: - fpath : location of the binary file
                      - fname : name of the binary file
  Remark: if only one input argument is given, the function assumes that it
  contains info about path AND filename!!
 
  And it returns:     - nx    : amount of elements in x-direction
                      - nz    : amount of elements in z-direction (or y-)
                      - data  : 2-D data stored in the file.
  
  By Jacques Ernst (2006)                                        ETH Zurich
 ==========================================================================