up #446
 - fix ensightgold
 - still a deadlock, @aancel could you have a look
fix #445
 - now ginac expression support a custom worldcomm
see #444 for an example
up #444
 - add some extra computation to check that everything is ok
 - had to find the deadlock #445 and #446
should work fine now except for hdf5 (@aancel)