KAZOO-2558 - move incoming faxes to modb

You use `Year:4/binary` in the pattern match, yet `is_integer(Year)` in the guard? I don't think this will ever run.

````
1> <<Year:4/binary, _/binary>> = <<"2010-abc">>.
<<"2010-abc">>
2> Year.
<<"2010">>
3> is_integer(Year).
false
````