- make regionName an optional constructor parameter, which eliminates
a separate set of constructors and construction tables. Adjust
internals to treat a missing/empty regionName as a no-op.
- pass in fallback dictionary content via new IOdictionary constructor
with a pointer
ENH: further relax check for matching number of processor dirs
- if the "numberOfSubdomains" entry is missing (or even zero)
ignore checks of processor dirs as meaningless.