[COOK-3822] - Fixing up sasl_relayhost example in README
[COOK-3822] - Fixing up sasl_relayhost example in README

Signed-off-by: Sean OMeara <4025b808ec3cf11e3d5c9a1a3bd1e7c4003cb3a1@opscode.com>

opscode-cookbooks/postfix,chef-cookbooks/postfix,heat-cookbooks/postfix,zuazo-forks/chef-cookbooks-postfix,voroniys/postfix,Maks3w/postfix,CarnegieLearningWeb/chef-postfix,Lostmyname/postfix,gnowxilef/cookbook-postfix,tejaycar/postfix,ianneub/postfix,chrisjbray/postfix,yakara-ltd/postfix,nilroy/postfix,brint/postfix,rackspace-cookbooks/rackspace_postfix,mawatech/postfix,CarnegieLearningWeb/chef-postfix,interactive-investor-ltd/postfix,tezz123/postfix,interactive-investor-ltd/postfix,mlyndaker/postfix,nilroy/postfix,chrisjbray/postfix,tcroiset/postfix,zuazo-forks/chef-cookbooks-postfix,leoditommaso/postfix,chef-cookbooks/postfix,leoditommaso/postfix,heat-cookbooks/postfix,gnowxilef/cookbook-postfix,opscode-cookbooks/postfix,rafaelmagu/postfix,yakara-ltd/postfix,voroniys/postfix,tas50/postfix,mawatech/postfix,harmdewit/postfix,Lostmyname/postfix,mlyndaker/postfix