add license information to the rake task that creates the gemspec
add license information to the rake task that creates the gemspec

Otherwise the license in the gemspec would get overwritten

rkh/addressable,Hacker0x01/addressable,sferik/addressable,shaicoleman/addressable,EiNSTeiN-/addressable,107191613/addressable,sporkmonger/addressable,davidbegin/addressable,iainbeeston/addressable