Comment 6 for bug 326541

i've added a generic StringListDlg that i would like to see used here instead of asking the user to put ';' to delimit extensions. this way, a simple list can be used everywhere and semicolons will only appear when interfacing with the settings file.
as for performance, there's almost no overhead to using a vector; actually, when micro-optimizing a vector may even be better than all the ';' chars... but the main reason to have a list here is not performance but plain logic; semicolons only make sense in the context of loading & saving to file.
the StringListDlg allows customization of the addition command (see the public hub list dlg for an example) so invalid extensions can be checked for when they are individually being entered instead of when validating the whole list.

as for the NMDC problem, i would like not having to see legacy types when i have selected only ADC hubs, but this can be thought of later on.