Ensure ALL diagnostics are bit comparable on different PE configurations.

Essentially this involves ensuring that ALL wrap columns in global models
are up to date at the point of writing diagnostics. Without this,
hundreds (!) of diagnostics feature wrap columns which contain uninitialised
data, the contents of which may vary with PE decomposition. Those are the
detectable ones. In the cases that diagnostics are actually initialised, it's
impossible to detect duff wrap column data w/o manually examining every
diagnostic. That then leads to questions about data integrity
(e.g. if someone daoes a global max or min operation on a field w/o
properly poplulated data they will get incorrect, and not necessarily
noticeable, information!)

Also remove redundant, duplicate computation and iom_put of 3D
diagnostic weiv_masstr.