DWDS/Dialing Concordance Code

- typo (misspelled)
- broken: removing virtual CHost::Close() layer bypasses subclass-specific cleanup code, can cause fd-leaks
- added utility method CloseSocketRef() analogous to r1329 'CloseSocketWraper' in string_socket.(h|cpp)
- re-factored default CHost::Close() to just call new CloseSocketRef()
- virtual method & other (virtual) (CHost*)->Close() calls unchanged