add message below ascii QR code to alert users to change their font if necessary; closes #632
add message below ascii QR code to alert users to change their font if necessary; closes #632

harlo/securedrop,jaseg/securedrop,ehartsuyker/securedrop,micahflee/securedrop,jrosco/securedrop,GabeIsman/securedrop,pwplus/securedrop,kelcecil/securedrop,ehartsuyker/securedrop,conorsch/securedrop,garrettr/securedrop,pwplus/securedrop,ehartsuyker/securedrop,GabeIsman/securedrop,chadmiller/securedrop,garrettr/securedrop,GabeIsman/securedrop,conorsch/securedrop,jrosco/securedrop,jrosco/securedrop,jeann2013/securedrop,chadmiller/securedrop,heartsucker/securedrop,pwplus/securedrop,jeann2013/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,chadmiller/securedrop,jeann2013/securedrop,harlo/securedrop,harlo/securedrop,kelcecil/securedrop,kelcecil/securedrop,micahflee/securedrop,jaseg/securedrop,ageis/securedrop,chadmiller/securedrop,heartsucker/securedrop,GabeIsman/securedrop,harlo/securedrop,conorsch/securedrop,chadmiller/securedrop,ageis/securedrop,jeann2013/securedrop,harlo/securedrop,jaseg/securedrop,heartsucker/securedrop,jaseg/securedrop,jaseg/securedrop,heartsucker/securedrop,jeann2013/securedrop,kelcecil/securedrop,jrosco/securedrop,jeann2013/securedrop,micahflee/securedrop,kelcecil/securedrop,GabeIsman/securedrop,jrosco/securedrop,ageis/securedrop,micahflee/securedrop,garrettr/securedrop,ageis/securedrop,pwplus/securedrop,chadmiller/securedrop,jaseg/securedrop,jrosco/securedrop,pwplus/securedrop,kelcecil/securedrop,pwplus/securedrop,GabeIsman/securedrop,garrettr/securedrop,harlo/securedrop,conorsch/securedrop,ehartsuyker/securedrop,heartsucker/securedrop,conorsch/securedrop