Remove all alpha in A-Number on USCIS PDF Form Fill

[tonybranfort]

Currently alpha chars (A-Z,a-z) are left in in A-Number (and other non numbers removed) when it is populated into USCIS PDF forms. So A555-877-370 will be filled as A555877370. It should be filled in as 555877370. This is only an issue for A-Nbrs filled into IDB prior to the edit requiring A-Nbrs to start with a number.