Report an error when writing a file with changing topology.

If the number of points, cells or blocks change from one time step to the next,
report an error. We modified the writer to suport temporal files with
changing topology, however the reader does not yet supports it.

Change-Id: Icf7528cf3507094658dbfa8076c670f396aa6989
Merge topic '14539-can-crash' into master

b604c23b Report an error when writing a file with changing topology.