Put the string manipuuation utils in the cpp, and
remove string_utils.h from the includes of netinfo.h.
This spams that header into about 350 files, not all of which
need it. Then go round and tidy up the places (most exporters
and dialogs) where CPP files weren't including string_utils.h
when they used it, as well as some other order-sensitive
include issues that turned up.
Recommendation is to avoid using the year nomenclature as this
information is already encoded in the git repo. Avoids needing to
repeatly update.
Also updates AUTHORS.txt from current repo with contributor names
