Added email domain verification. Will be generalized to organizations.
Added email domain verification. Will be generalized to organizations.

royragsdale/picoCTF,picoCTF/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,picoCTF/picoCTF,picoCTF/picoCTF,royragsdale/picoCTF,royragsdale/picoCTF,royragsdale/picoCTF