Fix new laravel installation error 500 error
http://stackoverflow.com/questions/20678360/laravel-blank-white-screen
go to the directory where laravel is installed then:
# Group Writable (Group, User Writable)
$ sudo chmod -R gu+w storage
# World-writable (Group, User, Other Writable) - FOR LOCALHOST ENVIRONMENT
$ sudo chmod -R guo+w storage