added requirements
added requirements

viniciusnz/savon,payfriendz/savon,BlaneCordes/savon_vertex,savonrb/savon,rtrepo/savon,mpangrazzi/savon,SICSoftwareGmbH/savon,zerobatu/savon,enahum/savon,latortuga/savon,oafridi/savon,advishnuprasad/savon,travis-repos/savon,Eric-Guo/savon,billr578/savon,kimptoc/Savon-with-username-token-digest