Comment 4 for bug 1016654

On the front of the listed options in comment #2:

#1 would work for per-service regex type deals fairly easily.

#2 could apply as well, but I still think a per-service config is needed, if only to validate that the correct number of digits was provided.

#3 and #4 are not portable outside of NANP numbers and I thus disagree with. We can't assume that Evergreen will only ever be used in the US and Canada type deal.