uuid required in sign_document but only available if the object was build (SAML Message), if we parse directly it was not available.  Related to #209
uuid required in sign_document but only available if the object was build (SAML Message), if we parse directly it was not available.  Related to #209

kaligrafy/ruby-saml,rightscale/ruby-saml,18F/ruby-saml,ylansegal/ruby-saml,yidimu/ruby-saml,zipnosis/ruby-saml,OurHealth/ruby-saml,jobscore/ruby-saml,InviteEducation/ruby-saml,onelogin/ruby-saml,greggersh/ruby-saml,stevecrozz/ruby-saml,itrp/ruby-saml,ksinkar/ruby-saml,alexandru-calinoiu/ruby-saml,Crushpath/ruby-saml,01Click/ruby-saml,10Kft/ruby-saml