Add travis build status badge to README
Add travis build status badge to README

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