add verbosities

[marc1uk]

add verbosity constants to Tool

[brichards64]

whats get_ok?

[marc1uk]

A Generic Boolean ™️
You always need a boolean for checking return of e.g. m_variables.Get(...) or m_data->Stores.Get(...) or some function call or other. It's just useful to not have to think of new names for booleans you make on one line and check on the next.