- ensure proper and sensible handling of empty names.
Eg, isDir(""), isFile("") are no-ops, and avoid file-stat
- rmDir:
* optional 'silent' option to suppress messages.
* removes all possible sub-entries, instead of just giving up on
the first problem encountered.
- reduced code duplication in etcFiles
ENH: provide WM_USER_RESOURCE_DIRNAME define (in foamVersion.H)
- this is still a hard-coded value, but at least centrally available